1996 Aerostar Abs Trouble Code Pinpoint Tests

1996 Ford Truck Aerostar AWD V6-245 4.0L

Copyright © 2008, ALLDATA

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Antilock Brakes / Traction Control Systems: Testing and Inspection Procedures Trouble Code Diagnostic Charts Pinpoint Test Notes

Assuming the red brake warning light diagnosis has been performed and passed, and the Rear Anti-lock Brake System (RABS) warning light is illuminated, the code retrieved is used to designate the appropriate pinpoint test. The pinpoint tests are relatively simple and will be effective in most situations. See:

If resolution is not reached by the end of the pinpoint test, additional, more in-depth procedures are provided in the drive tests. See: Monitors, Trips and/or Drive Cycle/Drive Test Description

System Pre Check

RABS Valve Connector And Pin View DESCRIPTION Code 2 is generated by the module's detection of an open circuit in Circuit 599 (PK/LG). The code may also be generated by a failed isolation solenoid (open coil) internal to the anti-lock brake control module or a failed internal module circuit. Possible Contributing Base Brake Component/Vehicle Wiring Concerns - Terminal backout in the module harness connector at Pin 13 - Terminal backout in the RABS valve harness connector at Pin 1 - Bulkhead connector (between engine compartment and instrument panel) terminal backout or loose connection - Anti-lock electronic control unit or RABS valve connectors not fully mated with component - Intermittent open circuit in Circuit 599 (PK/LG)

2.1 - Verify Integrity of Module Connection ^ Turn the ignition OFF. ^ Disconnect battery ground cable. ^ Remove the module connector. ^ Pull gently on Pin 13 (PK/LG) just behind the harness connector. ^ Is connector clean and secure? YES -- Leave anti-lock electronic control module connector disconnected. Go to 2.2. See: Code 2/2.2 - Verify Integrity of Valve Connection NO -- Service terminal or connector as needed. If terminals are not serviceable, replace anti-lock electronic control module. Go to 2.6. See: Code 2/2.6 - Clear Code/Pull Code

2.2 - Verify Integrity of Valve Connection ^ Remove RABS valve connector. ^ Inspect RABS valve component connector for contamination or loose terminals.

1996 Ford Truck Aerostar AWD V6-245 4.0L

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^ Pull gently on Pin 1 (PK/LG) just behind the harness connector. ^ Is terminal clean and secure? YES -- Leave RABS valve connector disconnected. Go to 2.3. See: Code 2/2.3 - Check For Continuity Along Harness Circuit 599 (PK/LG) NO -- Service terminal or connector as needed. If not serviceable, replace RABS valve. Go to 2.6. See: Code 2/2.6 - Clear Code/Pull Code

2.3 - Check For Continuity Along Harness Circuit 599 (PK/LG) ^ Verify multimeter is on 200-ohm scale. ^ Measure resistance between anti-lock electronic control module harness connector Pin 13 and RABS valve harness connector Pin 1. ^ Is resistance less than 10 ohms? YES -- Circuit is not open. GO to 2.4. See: Code 2/2.4 - Check For Open RABS Valve Isolation Solenoid NO -- Find and repair open circuit along circuit 599 (PK/LG). GO to 2.6. See: Code 2/2.6 - Clear Code/Pull Code

2.4 - Check For Open RABS Valve Isolation Solenoid ^ Verify multimeter is on 200-ohm scale. ^ Measure resistance between RABS valve Pins 1 and 3. ^ Is resistance less than 6 ohms? YES -- Circuit is not open. Go to 2.5. See: Code 2/2.5 - Make Sure All Steps Are Completed NO -- Open circuit in RABS valve. Replace RABS valve. Go to 2.6. See: Code 2/2.6 - Clear Code/Pull Code

2.5 - Make Sure All Steps Are Completed NOTE: Be sure to complete all steps. Failure to do so could lead to replacement of good components. ^ This step requires that a valid diagnostic trouble code has been obtained, all prior diagnostic steps have been completed, and the affected wiring integrity has been verified. ^ Have all prior diagnostic steps been completed as described above? YES -- Replace anti-lock electronic control module. Go to Step 2.6. See: Code 2/2.6 - Clear Code/Pull Code YES -- If anti-lock electronic control module has been replaced and no resolution has been reached, replace RABS valve. Go to Step 2.6. See: Code 2/2.6 - Clear Code/Pull Code NO -- GO to diagnostic step last completed and continue.

2.6 - Clear Code/Pull Code ^ Turn ignition OFF. ^ Reconnect battery ground cable. NOTE: When the battery ground cable has been disconnected and reconnected, some abnormal drive symptoms may occur while the Powertrain Control Module (PCM) (12A650) relearns its adaptive strategy. The vehicle may need to be driven 16 km (10 miles) or more to relearn the strategy. ^ Verify all connectors are installed. ^ Locate and disconnect the diagnostic connector from its mating half (Circuits 571 [BK/O] and 483 [R]). ^ Turn ignition ON. ^ Begin diagnostic trouble code flashout by connecting Circuit 571 (BK/O) to a chassis ground for at least 1 second. ^ Observe and count code.

1996 Ford Truck Aerostar AWD V6-245 4.0L

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^ Is Code 16 set? YES -- Go to Drive Test Code 16. NO -- If Code 2, GO to 2.7. See: Code 2/2.7 - Pinpoint Test Status If different code, Go to pinpoint test for corresponding code.

2.7 - Pinpoint Test Status ^ Has pinpoint test been completed? YES -- Go to 2.8. See: Code 2/2.8 - Verify Integrity of Vehicle Wiring NO -- Return to last pinpoint test completed.

2.8 - Verify Integrity of Vehicle Wiring If the previous pinpoint test steps have been completed, the most likely cause of the concern is wiring related.

RABS Valve Connector And Pin View ^ Refer to Pinpoint Test ID, Intermittent Diagnosis Procedure and perform for all affected circuits as shown on this pinpoint test system schematic. See: Component Tests ^ Is resolution achieved? YES -- Stop. Repair is complete. Go to drive test code 16. NO -- Go to 2.5. See: Code 2/2.6 - Clear Code/Pull Code

System Pre Check

DESCRIPTION

Connector Diagram

1996 Ford Truck Aerostar AWD V6-245 4.0L

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Code 3 is generated by the anti-lock electronic control module's detection of an open circuit in line 664 (Y/LG) or 274 (BK/W). The code may also be generated by a failed dump solenoid (open coil) internal to the RABS valve or a failed internal anti-lock electronic control module circuit. POSSIBLE CONTRIBUTING BASE BRAKE COMPONENT/VEHICLE WIRING CONCERNS ^ Terminal backout in the anti-lock electronic control module harness connector at Pins 8 or 14 ^ Terminal backout in the RABS valve harness connector at Pin 4 ^ Bulkhead connector (between engine compartment and instrument panel) terminal backout or loose connection ^ Anti-lock electronic control module or RABS valve connectors not fully mated with component ^ Intermittent open circuit in line 664 (Y/LG) NOTE: Use Rotunda(r) 73 Digital Multimeter 105-00051 or equivalent for electrical tests.

3.1 - Verify Integrity of Module Connection ^ Turn ignition to the OFF position. ^ Disconnect battery ground cable. ^ Remove the anti-lock electronic control module connector. ^ Inspect anti-lock electronic control module Pins 8 and 14. ^ Pull gently on each wire just behind Pins 8 and 14 on harness connector. ^ Are connections clean and secure? YES -- Leave anti-lock electronic control module connector disconnected. Go to 3.2. See: Code 3/3.2 - Verify Integrity of Valve Connection NO -- Terminal(s) in anti-lock electronic control module connector are loose, bent, deformed, corroded, or missing. Service terminal or connector as needed. NO -- If not serviceable, replace anti-lock electronic control module. Go to 3.6. See: Code 3/3.6 - Clear Code/Pull Code NO -- Terminals 8 or 14 in harness connector move back or come free of connector. Service terminal or connector as needed. Go to 3.6. See: Code 3/3.6 - Clear Code/Pull Code

3.2 - Verify Integrity of Valve Connection ^ Remove RABS valve connector. ^ Inspect RABS valve connector Pin 4. ^ Gently pull on Pin 4 wire just behind harness connector. ^ Are connections clean and secure? YES -- Leave RABS valve connector disconnected. Go to 3.3. See: Code 3/3.3 - Check For Continuity Along Harness Circuits NO -- Terminal(s) in RABS valve connector are loose, bent, deformed, corroded, or missing. Service terminal or connector as needed. If not serviceable, Replace RABS valve. Go to 3.6. See: Code 3/3.6 - Clear Code/Pull Code NO -- Terminal(s) in harness connector move back or come free of connector. Service terminal or connector as needed. Go to 3.6. See: Code 3/3.6 - Clear Code/Pull Code

3.3 - Check For Continuity Along Harness Circuits ^ Set multimeter on 200-ohm scale. ^ Measure resistance between anti-lock electronic control module harness connector Pin 8 and RABS valve harness connector Pin 4. ^ Measure resistance between anti-lock electronic module harness connector Pin 14 and RABS valve harness connector Pin 4. ^ Is resistance less than 1 ohm? YES -- Circuit is not open. Go to 3.4. See: Code 3/3.4 - Check For Open RABS Dump Valve Solenoid

1996 Ford Truck Aerostar AWD V6-245 4.0L

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NO -- Find and repair open circuit along 664 (Y/LG). Go to 3.6. See: Code 3/3.6 - Clear Code/Pull Code

3.4 - Check For Open RABS Dump Valve Solenoid ^ Verify multimeter is on 200-ohm scale. ^ Measure resistance between RABS valve Pins 4 and 3. ^ Is resistance less than 3 ohms? YES -- Circuit is not open. go to 3.5. See: Code 3/3.5 - Make Sure All Steps Are Completed NO -- Open circuit in RABS is indicated. Replace RABS valve. Go to 3.6. See: Code 3/3.6 - Clear Code/Pull Code

3.5 - Make Sure All Steps Are Completed NOTE: Be sure to complete all steps. Failure to do so may lead to replacement of good parts. ^ This step requires that a valid diagnostic trouble code has been obtained, all prior diagnostic steps have been completed, and the affected wiring integrity has been verified. ^ Have all prior diagnostic steps been completed as described above? YES -- Replace anti-lock electronic control module. Go to Step 3.6. See: Code 3/3.6 - Clear Code/Pull Code YES -- If anti-lock electronic control module has been replaced and no resolution has been reached, Replace RABS valve. Go to step 3.6. See: Code 3/3.6 - Clear Code/Pull Code NO -- Go to diagnostic step last completed and continue.

3.6 - Clear Code/Pull Code NOTE: When the battery ground cable has been disconnected and reconnected, some abnormal drive symptoms may occur while the powertrain control module relearns its adaptive strategy. The vehicle may need to be driven 16 km (10 miles) or more to relearn the strategy. ^ Turn ignition OFF. ^ Reconnect battery ground cable. ^ Verify all connectors are installed. ^ Locate and disconnect the diagnostic connector from its mating half (Circuits 571 [BK/O] and 483 [R]). ^ Turn ignition ON. ^ Begin diagnostic trouble code flashout by connecting Circuit 571 (BK/O) to a chassis ground for at least 1 second. ^ Observe and count code. ^ Is Code 16 set? YES -- GO to Drive Test Code 16. NO -- If Code 2, GO to 3.7. See: Code 3/3.7 - Pinpoint Test Status If different code, Go to pinpoint test for corresponding code.

3.7 - Pinpoint Test Status ^ Have all prior pinpoint tests been completed? YES -- GO to 3.8. See: Code 3/3.8 - Verify Integrity of Vehicle Wiring NO -- Return to last pinpoint test completed.

3.8 - Verify Integrity of Vehicle Wiring NOTE: If the previous pinpoint test steps have been completed, the most likely cause of the concern is wiring related.

1996 Ford Truck Aerostar AWD V6-245 4.0L

Copyright © 2008, ALLDATA

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Connector Diagram ^ Refer to Pinpoint Test ID, Intermittent Diagnosis Procedure and perform for all affected circuits as shown on this pinpoint test system schematic. See: Component Tests ^ Is resolution achieved? YES -- Stop. Repair is complete. Go to drive test code 16. NO -- Go to 3.5. See: Code 3/3.5 - Make Sure All Steps Are Completed

System Pre Check

Connector

DESCRIPTION Code 4 is generated by the anti-lock electronic control module's detection of a resistance falling below 18k Ohms (short) or above 26 k Ohms (open) in Circuit 535 (LB/R). This can indicate an open or short in the reset switch circuit, or a hydraulic leak into dump section of the valve. POSSIBLE CONTRIBUTING BASE BRAKE COMPONENT/VEHICLE WIRING CONCERNS ^ Terminal backout in the module harness connector at Pin 6 ^ Terminal backout in the RABS valve harness connector at Pins 2 or 3 ^ Bulkhead connector (between engine compartment and instrument panel) terminal backout or loose connection ^ Anti-lock electronic control module or RABS valve connectors not fully mated with component ^ Intermittent open or open circuit in Circuits 535 (LB/R), or 274 (BK/W) ^ Intermittent short or short circuit in Circuit 535 (LB/R) ^ Defective RABS valve NOTE: Use Rotunda(r) 73 Digital Multimeter 105-00051 or equivalent for electrical tests.

4.1 - Verify Integrity of RABS Valve Connection ^ Remove RABS valve connector.

1996 Ford Truck Aerostar AWD V6-245 4.0L

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^ Inspect RABS valve component connector Pins 2 and 3. ^ Inspect RABS valve harness connector Pins 2 and 3. ^ Pull gently on Pin 2 wire just behind the harness connector. ^ Pull gently on Pin 3 just behind the harness connector. ^ Are connections clean and secure? YES -- Leave RABS valve connector disconnected. Go to 4.2. See: Code 4/4.2 - Verify Integrity of Anti-Lock Electronic Control Module NO -- Terminals in RABS valve connector are loose, bent, deformed, corroded, or missing. Service terminal or connector as needed. If not serviceable, Replace RABS valve. GO to 4.10. See: Code 4/4.10 - Clear Code/Pull Code NO -- Terminal(s) in harness connector move back or come free of connector. Service terminal or connector as needed. Go to 4.10. See: Code 4/4.10 - Clear Code/Pull Code

4.2 - Verify Integrity of Anti-Lock Electronic Control Module ^ Turn the ignition OFF. ^ Disconnect battery ground cable. ^ Inspect anti-lock electronic control module component connector Pin 6. ^ Inspect anti-lock electronic control module harness connector Pin 6. ^ Pull gently on Pin 6 wire just behind the harness connector. ^ Are connections clean and secure? YES -- Leave anti-lock electronic control module connector disconnected. GO to 4.3. See: Code 4/4.3 - Check For Continuity Along Harness Circuit 535 (Lb/R) NO -- Terminal(s) in anti-lock electronic control module connector are loose, bent, deformed, corroded, or missing. Service terminal or connector as needed. NO -- If not serviceable, Replace anti-lock electronic control module. Go to 4.10. See: Code 4/4.10 - Clear Code/Pull Code NO -- Terminal 6 in harness connector moves back or comes free of connector. Service terminal or connector as needed. Go to 4.10. See: Code 4/4.10 - Clear Code/Pull Code

4.3 - Check For Continuity Along Harness Circuit 535 (Lb/R) ^ Set multimeter on 200-ohm scale. ^ Measure resistance between anti-lock electronic control module harness connector Pin 6 and RABS valve harness connector Pin 2. ^ Is resistance less than 10 ohms? YES -- Circuit is not open. GO to 4.4. See: Code 4/4.4 - Check For Continuity Along Ground Circuit 274 (BK/W) NO -- Find and repair open circuit along circuit 535 (LB/R). Go to 4.10. See: Code 4/4.4 - Check For Continuity Along Ground Circuit 274 (BK/W)

4.4 - Check For Continuity Along Ground Circuit 274 (BK/W) ^ Set multimeter on 200-ohm scale. ^ Measure resistance between RABS valve harness connector Pin 3 and negative battery post. ^ Is resistance 3 ohms or less? YES -- Circuit is not open. Go to 4.5. See: Code 4/4.5 - Check For Short Along Harness Circuit 535 (Lb/R)

1996 Ford Truck Aerostar AWD V6-245 4.0L

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NO -- Find and repair open circuit along circuit 274 (BK/W). Go to 4.10. See: Code 4/4.10 - Clear Code/Pull Code

4.5 - Check For Short Along Harness Circuit 535 (Lb/R) ^ Set multimeter on 200-ohm scale. ^ Measure resistance between module harness connector Pin 6 and chassis ground. ^ Is resistance greater than 12 ohms? YES -- Circuit is not shorted. GO to 4.6. See: Code 4/4.6 - Check For Closed RABS Valve Reset Switch NO -- Find and repair short circuit along circuit 535 (LB/R). Go to 4.10. See: Code 4/4.10 - Clear Code/Pull Code

4.6 - Check For Closed RABS Valve Reset Switch ^ Verify multimeter is on 200k Ohm scale. ^ Measure resistance between RABS valve connector Pin 2 and RABS valve body. ^ Is resistance greater than 10 k Ohms? YES -- Reset switch is not closed. GO to 4.7. See: Code 4/4.7 - Check For Hydraulic Leak In Dump Section of Valve NO -- Shorted circuit in RABS valve is indicated. Replace RABS valve. Go to 4.10. See: Code 4/4.10 - Clear Code/Pull Code

4.7 - Check For Hydraulic Leak In Dump Section of Valve ^ Set multimeter on 200k Ohm scale. ^ Check resistance between RABS valve Pin 2 and RABS valve body with hydraulic pressure applied for at least 30 seconds. ^ Is resistance greater than 10 k Ohms? YES -- Go to 4.8. See: Code 4/4.8 - Check Resistance Between Valve Switch and Valve Common NO -- Replace RABS valve. Go to 4.10. See: Code 4/4.10 - Clear Code/Pull Code

4.8 - Check Resistance Between Valve Switch and Valve Common ^ Verify multimeter is on 30k Ohm scale. ^ Measure resistance between RABS valve Pins 2 and 3. ^ Is resistance between 18-26k Ohms for aluminum RABS valve? YES -- RABS valve internal circuit is OK. Reinstall all connectors. Go to drive test code 4.9. See: Code 4/4.9 - Make Sure All Steps Are Completed NO -- Shorted or open circuit in RABS valve is indicated. Replace RABS valve. Go to 4.9. See: Code 4/4.9 - Make Sure All Steps Are Completed

4.9 - Make Sure All Steps Are Completed ^ This step requires that a valid diagnostic trouble code has been obtained, all prior diagnostic steps have been completed, and the affected wiring integrity has been verified. CAUTION: Make sure to complete all steps. Failure to do so could lead to replacement of good parts. ^ Have all prior diagnostic steps been completed as described above? YES -- Replace anti-lock electronic control module. Go to step 4.10. See: Code 4/4.10 - Clear Code/Pull Code YES -- If anti-lock electronic control module has been replaced and no resolution has been reached, Replace RABS valve. Go to Step 4.10. See: Code 4/4.10 - Clear Code/Pull Code NO -- GO to diagnostic step last completed and continue.

1996 Ford Truck Aerostar AWD V6-245 4.0L

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4.10 - Clear Code/Pull Code NOTE: When the battery ground cable has been disconnected and reconnected, some abnormal drive symptoms may occur while the powertrain control module relearns its adaptive strategy. The vehicle may need to be driven 16 km (10 miles) or more to relearn the strategy. ^ Turn ignition OFF. ^ Reconnect battery ground cable. ^ Verify all connectors are installed. ^ Locate and disconnect the diagnostic connector from its mating half (Circuits 571 (BK/O) and 483 (R). ^ Turn ignition ON. ^ Begin diagnostic trouble code flashout by connecting Circuit 571 (BK/O) to a chassis ground for at least 1 second. ^ Observe and count code. ^ Is Code 16 set? YES -- Go to drive test code 16. NO -- If code 4, go to 4.11. See: Code 4/4.11 - Verify Pinpoint Test Is Complete If different code, go to pinpoint test for corresponding code.

4.11 - Verify Pinpoint Test Is Complete ^ Have all prior pinpoint tests been completed? YES -- Go to 4.12. See: Code 4/4.12 - Verify Integrity of Vehicle Wiring NO -- Go to 4.5. See: Code 4/4.5 - Check For Short Along Harness Circuit 535 (Lb/R)

4.12 - Verify Integrity of Vehicle Wiring NOTE: If the previous pinpoint test steps have been completed, the most likely cause of the concern is wiring related.

Connector ^ Refer to Pinpoint Test ID, Intermittent Diagnosis Procedure and perform for all affected circuits as shown on the Pinpoint Test system schematic. See: Component Tests ^ Is resolution achieved? YES -- Go to drive test code 16. NO -- Go to drive test code 4.

System Pre Check

1996 Ford Truck Aerostar AWD V6-245 4.0L

Copyright © 2008, ALLDATA

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Connector Diagram

DESCRIPTION Code 5 is generated when the maximum number of allowable dump pulses has been exceeded. The system will only recognize this condition during an anti-lock stop in 2WD mode. The code may be caused by a blocked RABS dump valve orifice, a stuck dump valve, an open circuit in Circuit 210 (LB), a worn or damaged 4x4 transfer case that causes the vehicle to remain in 4x4 after 4x2 has been selected, or mechanical problems in the rear brake system. (Rear brake drums may lock.)

POSSIBLE CONTRIBUTING BASE BRAKE COMPONENT/VEHICLE WIRING CONCERNS ^ Parking brake drag ^ Worn or damaged 4x4 switch ^ Rear brake assembly grabbing or hanging up ^ Connector corrosion or contamination ^ Intermittent open circuit in Circuit 210 (LB) ^ Pierced wire insulation to battery power (4x4 only)

5.1 - Drive Status ^ Determine if vehicle is in 2-or 4-wheel drive when code occurred. ^ Is vehicle in 4-wheel drive? YES -- Go to 5.2. See: Code 5/5.2 - Incorrect 4WD Switch Signal/RABS Cntrl Unit Short to PWR NO -- Go to 5.3. See: Code 5/5.3 - Check For Low or Erratic Sensor Signal

5.2 - Incorrect 4WD Switch Signal/RABS Cntrl Unit Short to PWR ^ Disconnect RABS II module harness connector from anti-lock electronic control unit to deactivate RABS. ^ Key ON. ^ Shift into 4x4 mode. ^ Set voltmeter to 20VDC scale. ^ Measure voltage between Pin 5 of the module harness and chassis ground. ^ Is the measured voltage less than 1V? YES -- Go to 5.3. See: Code 5/5.3 - Check For Low or Erratic Sensor Signal NO -- Repair 4x4 indicator switch or Repair short in the 4x4 indicator switch Circuit 210 (LB). Go to 5.4. See: Code 5/5.4 - Make Sure All Steps Are Completed

5.3 - Check For Low or Erratic Sensor Signal ^ Disconnect module harness connector. ^ Position vehicle on hoist and raise both front and rear wheels just enough to clear the floor.

1996 Ford Truck Aerostar AWD V6-245 4.0L

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^ Start the engine (6007) and turn the wheels at 5 mph. ^ Place voltmeter on 2000mV AC scale. ^ Measure the voltage across module harness connector Pins 3 and 10. ^ Is the voltage less than 650mV RMS or is sensor signal erratic? YES -- Complete pinpoint test for Code 6, steps 6.2 through 6.8. See: Code 6 Go to 5.4 to verify. See: Code 5/5.4 - Make Sure All Steps Are Completed NO -- Reinstall module connector. Go to drive test for Code 5.

5.4 - Make Sure All Steps Are Completed NOTE: If the above is not complete, chances are that replacement of this or any other system component without specific direction will not, in most circumstances, resolve the concern and will consequently result in customer dissatisfaction. ^ This step requires that a valid diagnostic trouble code has been obtained, all prior diagnostic steps have been completed, and the affected wiring integrity has been verified. ^ Have all prior diagnostic steps been completed as described above? YES -- Replace anti-lock electronic control unit. Go to Step 5.5. NOTE: If anti-lock electronic control unit has been replaced and no resolution has been reached, Replace RABS Valve. Go to Step 5.5. See: Code 5/5.5 - Clear Code/Pull Code NO -- Go to diagnostic step last completed and continue.

5.5 - Clear Code/Pull Code NOTE: When the battery ground cable has been disconnected and reconnected, some abnormal drive symptoms may occur while the powertrain control module relearns its adaptive strategy. The vehicle may need to be driven 10 miles or more to relearn the strategy. ^ Turn ignition OFF. ^ Reconnect battery ground cable. ^ Verify all connectors are installed. ^ Locate and disconnect the diagnostic connector from its mating half (Circuits 571 [BK/O] and 481 [R]). ^ Turn ignition ON. ^ Begin diagnostic trouble code flashout by connecting Circuit 571 (BK/O) to a chassis ground for at least 1 second. ^ Observe and count code. ^ Is Code 16 set? YES -- Go to Drive Test Code 16. NO -- If Code 5, Go to 5.6. See: Code 5/5.6 - Pinpoint Test Status If different Go to pinpoint test for corresponding code. See: Trouble Code Descriptions

5.6 - Pinpoint Test Status ^ Have all prior pinpoint tests been completed? YES -- Go to 5.7. See: Code 5/5.7 - Verify Integrity of Vehicle Wiring NO -- return to last pinpoint test completed.

5.7 - Verify Integrity of Vehicle Wiring NOTE: If the previous pinpoint test steps have been completed, the most likely cause of the concern is wiring related.

1996 Ford Truck Aerostar AWD V6-245 4.0L

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Connector Diagram ^ Refer to the Intermittent Wiring Diagnosis Procedure and perform for all affected circuits as shown on this mini-schematic. ^ Is resolution achieved? YES -- Stop. Repair is complete Go to Drive Test Code 16. NO -- Go to 5.4. See: Code 5/5.4 - Make Sure All Steps Are Completed

System Pre Check

Connector Diagram

DESCRIPTION Code 6 is generated by the anti-lock electronic control module's detection of an interruption in the continuous signal from the speed sensor while rolling, caused by an intermittent open internal to the speed sensor, Circuit 519 (LG/BK) or Circuit 523 (R/PK), or a damaged speed sensor ring. This condition can be detected anytime the brake pedal (2455) is not applied and 20 seconds has elapsed since the ignition self-test.

POSSIBLE CONTRIBUTING BASE BRAKE COMPONENT/VEHICLE WIRING CONCERNS ^ Terminal backout in the anti-lock electronic control module harness connector at Pins 3 and 10 ^ Terminal backout in the RABS speed sensor harness connector at Pins A and B ^ Bulkhead connector (between engine compartment and instrument panel) terminal backout or loose connection ^ Anti-lock electronic control module or RABS speed sensor connectors are not fully mated with component ^ Intermittent open/short circuit in Circuits 519 (LG/BK) or 523 (R/PK) ^ Damaged speed sensor (possibly metal shavings on pole piece) ^ Damaged speed sensor ring (possibly teeth missing) NOTE: Use Rotunda(r) 73 Digital Multimeter 105-00051 or equivalent for electrical tests.

6.1 - Verify Integrity of Module Connection

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^ Turn ignition OFF. ^ Disconnect battery ground cable. ^ Remove the anti-lock electronic control module connector. ^ Inspect anti-lock electronic control module component connector for contamination and loose or bent terminals. ^ Pull gently on Circuit 519 (LG/BK) just behind Pin 3 on the harness connector. ^ Pull gently on Circuit 523 (R/PK) just behind Pin 10 on the harness connector. ^ Are all connections clean and secure? YES -- Leave anti-lock electronic control module connector disconnected. GO to 6.2. See: Code 6/6.2 - Verify Integrity of Sensor Connection NO -- Terminal(s) in component connector are corroded, bent, or loose. service terminals or connector as needed. If not serviceable replace anti-lock electronic control module. GO to 6.7. See: Code 6/6.7 - Make Sure All Steps Are Completed NO -- Terminal(s) in harness connector are corroded, bent, or move back or come free of connector. Service terminals or connector as needed. GO to 6.7. See: Code 6/6.7 - Make Sure All Steps Are Completed

6.2 - Verify Integrity of Sensor Connection ^ Verify ignition is OFF. ^ Remove speed sensor connector. ^ Inspect speed sensor component connector for contamination and bent or loose terminals. ^ Gently pull on Circuit 519 (LG/BK) behind Pin B of harness connector. ^ Gently pull on Circuit 523 (R/PK) behind Pin A of harness connector. ^ Are all connections clean and secure? YES -- Reinstall RABS speed sensor connector. Go to 6.3. See: Code 6/6.3 - Verify Proper Sensor Wire Routing NO -- Terminal(s) in component connector are corroded, bent, or loose. Service terminal or connector as needed. If not serviceable, replace RABS speed sensor. Go to 6.7. See: Code 6/6.7 - Make Sure All Steps Are Completed NO -- Terminal(s) in harness connector are corroded, bent, or move back or come free of connector. Service terminal or connector as needed. Go to 6.7. See: Code 6/6.7 - Make Sure All Steps Are Completed

6.3 - Verify Proper Sensor Wire Routing ^ Inspect wire routing. ^ Are wires clean and secure? YES -- Go to 6.4. See: Code 6/6.4 - Verify Sensor Integrity NO -- Repair as necessary. Go to 6.7. See: Code 6/6.7 - Make Sure All Steps Are Completed

6.4 - Verify Sensor Integrity ^ Set multimeter on the 20k Ohm scale. ^ Check resistance between Pins A and B of the sensor connector. ^ Is resistance between 900 and 2500 ohms? YES -- Go to 6.5. See: Code 6/6.5 - Check For Erratic Sensor Signal and Loose Wire Connectors NO -- Replace RABS speed sensor. Go to 6.6. See: Code 6/6.6 - Check For Metal Chips on Sensor Magnet Pole Piece

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6.5 - Check For Erratic Sensor Signal and Loose Wire Connectors ^ Set multimeter on the 20k Ohm scale. ^ Check resistance between Pin 10 and Pin 3 of the harness connector while shaking the harness from sensor to anti-lock electronic control module. ^ Is reading steady and between 900 and 2500 ohms? YES -- Signal is not erratic. Go to 6.6. See: Code 6/6.6 - Check For Metal Chips on Sensor Magnet Pole Piece NO -- Find and repair open/short circuit along circuits 519 (LG/BK) and 523 (R/PK). Go to 6.7. See: Code 6/6.7 - Make Sure All Steps Are Completed

6.6 - Check For Metal Chips on Sensor Magnet Pole Piece ^ Verify ignition is OFF. ^ Remove the speed sensor from the rear axle housing (4010) and inspect for a buildup of metal chips on speed sensor magnetic pole. ^ Are metal chips present? YES -- Drain and clean rear axle housing. Go to 6.7. See: Code 6/6.7 - Make Sure All Steps Are Completed NO -- Leave speed sensor out. Go to 6.7. See: Code 6/6.7 - Make Sure All Steps Are Completed

6.7 - Make Sure All Steps Are Completed ^ This step requires that a valid diagnostic trouble code has been obtained, all prior diagnostic steps have been completed, and the affected wiring integrity has been verified. CAUTION: Make sure to complete all test steps. Failure to do so could cause replacement of good parts. ^ Have all prior diagnostic steps been completed as described above? YES -- Replace anti-lock electronic control module. Go to Step 6.8. See: Code 6/6.8 - Clear Code/Pull Code YES -- If anti-lock electronic control module has been replaced and no resolution has been reached, replace rear axle speed sensor. Go to step 6.8. See: Code 6/6.8 - Clear Code/Pull Code NO -- Go to diagnostic step last completed and continue.

6.8 - Clear Code/Pull Code NOTE: When the battery ground cable has been disconnected and reconnected, some abnormal drive symptoms may occur while the powertrain control module relearns its adaptive strategy. The vehicle may need to be driven 10 miles or more to relearn the strategy. ^ Turn ignition OFF. ^ Reconnect battery ground cable. ^ Verify all connectors are installed. ^ Locate and disconnect the diagnostic connector from its mating half (Circuits 571 [BK/O] and 481 [R]). ^ Turn ignition ON. ^ Begin diagnostic trouble code flashout by connecting Circuit 571 (BK/O) to a chassis ground for at least 1 second. ^ Observe and count code. ^ Is Code 16 set? YES -- Go to Drive Test Code 16. NO -- If Code 6, Go to 6.9. See: Code 6/6.9 - Pinpoint Test Status If different code, Go to pinpoint test for corresponding code. See: Trouble Code Descriptions

6.9 - Pinpoint Test Status

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^ Have all prior pinpoint tests been completed? YES -- Go to 6.10. See: Code 6/6.10 - Verify Integrity of Vehicle Wiring NO -- Return to last pinpoint test completed.

6.10 - Verify Integrity of Vehicle Wiring NOTE: If all the steps for Code 6 have been completed, the most likely cause of the concern is wiring related.

Connector Diagram ^ Refer to the Intermittent Wiring Diagnosis Procedure and perform for all affected circuits as shown on this pinpoint test mini-schematic. See: Component Tests ^ Is resolution achieved? YES -- Stop. Repair is complete Go to Drive Test Code 16. NO -- Go to Drive Test. See: Monitors, Trips and/or Drive Cycle/Drive Test Description

System Pre Check

RABS Valve Connector And Pin View DESCRIPTION Code 7 is generated when the anti-lock electronic control module detects a missing isolation solenoid output. This can only be detected during an ignition self-check or during a RABS stop. POSSIBLE CONTRIBUTING BASE BRAKE COMPONENT/VEHICLE WIRING CONCERNS ^ Module internal fuse blown or internal open circuit ^ Shorted isolation solenoid internal to the RABS valve ^ Intermittent short or shorted circuit in Circuit 599 (PK/LG)

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^ Contamination or bent Pins 1 and 3 of RABS valve connector shorting together NOTE: Use Rotunda(r) 73 Digital Multimeter 105-00051 or equivalent for electrical tests.

7.1 - RABS Valve Isolation Solenoid or Wiring Shorted to Ground ^ Turn the ignition OFF. ^ Disconnect battery ground cable. ^ Remove the anti-lock electronic control module connector. ^ Set the multimeter on the 200-ohm scale. ^ Measure the resistance between anti-lock electronic control module harness connector Pin 13 and chassis ground. ^ Is resistance 3-6 ohms? YES -- Circuit is shorted. Leave module connector disconnected. Go to 7.2. See: Code 7/7.2 - Check Integrity of Valve Connection NO -- Resistance is less than 3 ohms. Circuit is not shorted. Leave module connector disconnected. Go to 7.5. See: Code 7/7.5 - Make Sure All Steps Are Completed

7.2 - Check Integrity of Valve Connection ^ Remove RABS valve connector. ^ Inspect RABS valve component connector and Pins 1 and 3. ^ Are connections clean and secure? YES -- Circuit is not shorted. Leave RABS valve connector disconnected. GO to 7.3. See: Code 7/7.3 - Check For Shorted RABS Isolation Solenoid NO -- Service terminals or connector as needed. If not serviceable, Replace RABS valve. Go to 7.6. See: Code 7/7.6 - Clear Code/Pull Code

7.3 - Check For Shorted RABS Isolation Solenoid ^ Verify RABS valve connector removed. ^ Set the multimeter on the 200-ohm scale. ^ Measure the resistance between Pins 1 and 3 of RABS valve connector. ^ Is resistance 3 or 6 ohms? YES -- Leave RABS valve connector disconnected. Go to 7.4. See: Code 7/7.4 - Check For Short to Ground Along Harness Circuit 599 NO -- Replace RABS valve. Go to 7.6. See: Code 7/7.6 - Clear Code/Pull Code

7.4 - Check For Short to Ground Along Harness Circuit 599 ^ Set multimeter on 20k Ohm scale. ^ Measure resistance between anti-lock electronic control module harness connector Pin 13 (PK/LG) and chassis ground. ^ Is resistance less than 20 k Ohms? YES -- Repair short in Circuit 599 (PK/LG) between anti-lock electronic control module and RABS valve. GO to 7.6. See: Code 7/7.6 Clear Code/Pull Code NO -- Conflict of information. Repeat 7.2. See: Code 7/7.2 - Check Integrity of Valve Connection

7.5 - Make Sure All Steps Are Completed ^ This step requires that a valid diagnostic trouble code has been obtained, all prior diagnostic steps have been completed, and the affected wiring integrity has been verified.

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CAUTION: Make sure to complete all steps. Failure to do so could lead to replacement of good parts. ^ Have all prior diagnostic steps been completed as described above? YES -- Replace anti-lock electronic control module. Go to Step 7.6. See: Code 7/7.6 - Clear Code/Pull Code YES -- If anti-lock electronic control module has been replaced and no resolution has been reached, Replace RABS valve. Go to Step 7.6. See: Code 7/7.6 - Clear Code/Pull Code NO -- Go to diagnostic step last completed and continue.

7.6 - Clear Code/Pull Code NOTE: When the battery ground cable has been disconnected and reconnected, some abnormal drive symptoms may occur while the powertrain control module relearns its adaptive strategy. The vehicle may need to be driven 16 km (10 miles) or more to relearn the strategy. ^ Turn ignition OFF. ^ Reconnect battery ground cable. ^ Verify all connectors are installed. ^ Locate and disconnect the diagnostic connector from its mating half (Circuits 571 [BK/O] and 481 [R]). ^ Turn ignition ON. ^ Begin diagnostic trouble code flashout by connecting Circuit 571 (BK/O) to a chassis ground for at least 1 second. ^ Observe and count code. ^ Is DTC 16 present? YES -- Go to drive test code 16. NO -- If Code 7, GO to 7.7. See: Code 7/7.7 - Pinpoint Test Status If different code, go to pinpoint test for corresponding code.

7.7 - Pinpoint Test Status ^ Have all prior pinpoint tests been completed? YES -- Go to 7.8. See: Code 7/7.8 - Verify Integrity of Vehicle Wiring NO -- Return to last pinpoint test completed.

7.8 - Verify Integrity of Vehicle Wiring NOTE: If the previous pinpoint test steps have been completed, the most likely cause of the concern is wiring related.

Connector Diagram ^ Refer to Pinpoint Test ID, Intermittent Diagnosis Procedure and perform for all affected circuits as shown on this pinpoint test system schematic. See: Component Tests

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^ Is resolution achieved? YES -- Stop. Repair is complete, Go to drive test code 16. NO -- Go to 7.5. See: Code 7/7.5 - Make Sure All Steps Are Completed

System Pre Check

Connector Diagram

DESCRIPTION Code 8 is generated when the anti-lock electronic control module detects a missing dump solenoid output. This concern can only be detected during an ignition self-test or during a RABS stop.

POSSIBLE CONTRIBUTING BASE BRAKE COMPONENT/VEHICLE WIRING CONCERNS ^ Anti-lock electronic control module internal fuse blown or internal open circuit ^ Shorted dump solenoid internal to RABS valve ^ Intermittent short or shorted circuit in Circuit 664 (Y/LG) ^ Bulkhead connector between engine compartment and instrument panel terminals shorted NOTE: Use Rotunda(r) 73 Digital Multimeter 105-00051 or equivalent for electrical tests.

8.1 - Check RABS Dump Solenoid or Wiring Short to GND ^ Turn the ignition OFF. ^ Disconnect battery ground cable. ^ Remove the anti-lock electronic control module connector. ^ Set the multimeter on the 200-ohm scale. ^ Measure the resistance between anti-lock electronic control module harness connector Pin 8 and chassis ground. ^ Measure the resistance between anti-lock electronic control module harness connector Pin 14 and chassis ground. ^ Is resistance between 1 and 3 ohms? YES -- Leave anti-lock electronic control module connector disconnected. Go to 8.4. See: Code 8/8.4 - Make Sure All Steps Are Completed NO -- Leave anti-lock electronic control module connector disconnected. Go to 8.2. See: Code 8/8.2 - Check For Shorted RABS Dump Solenoid

8.2 - Check For Shorted RABS Dump Solenoid ^ Remove RABS valve connector. ^ Set the multimeter on the 200-ohm scale.

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^ Measure the resistance between Pins 3 and 4 of RABS valve connector. ^ Is resistance greater than 1 ohm? YES -- Leave RABS valve connector disconnected. Go to 8.3. See: Code 8/8.3 - Check For Short to GRND Along Harness Circuit 664 NO -- Replace RABS valve. Go to 8.5. See: Code 8/8.5 - Clear Code/Pull Code

8.3 - Check For Short to GRND Along Harness Circuit 664 ^ Set multimeter on 20-ohm scale. ^ Measure resistance to ground between anti-lock electronic control module harness connector Pin 8 and valve harness connector Pin 4. ^ Measure resistance to ground between module harness connector Pin 14 and valve harness connector Pin 4. ^ Is resistance less than 10 ohms? YES -- Repair short in Circuit 664 (Y/LG) between anti-lock electronic control module and RABS valve. Go to 8.5. See: Code 8/8.5 - Clear Code/Pull Code NO -- Conflict of information. Repeat 8.1. See: Code 8/8.1 - Check RABS Dump Solenoid or Wiring Short to GND

8.4 - Make Sure All Steps Are Completed ^ This step requires that a valid diagnostic trouble code has been obtained, all prior diagnostic steps have been completed, and the affected wiring integrity has been verified. NOTE: Make sure to complete all steps. Failure to do so could lead to replacement of good parts. ^ Have all prior diagnostic steps been completed as described above? YES -- Replace anti-lock electronic control module. Go to step 8.5. See: Code 8/8.5 - Clear Code/Pull Code YES -- If anti-lock electronic control module has been replaced and no resolution has been reached, replace RABS valve. Go to Step 8.5. See: Code 8/8.5 - Clear Code/Pull Code NO -- Go to diagnostic step last completed and continue.

8.5 - Clear Code/Pull Code NOTE: When the battery ground cable has been disconnected and reconnected, some abnormal drive symptoms may occur while the powertrain control module relearns its adaptive strategy. The vehicle may need to be driven 16 km (10 miles) or more to relearn the strategy. ^ Turn ignition OFF. ^ Reconnect battery ground cable. ^ Verify all connectors are installed. ^ Locate and disconnect the diagnostic connector from its mating half (Circuits 571 [BK/O] and 483 [R]). ^ Turn ignition ON. ^ Begin diagnostic trouble code flashout by connecting Circuit 571 (BK/O) to a chassis ground for at least 1 second. ^ Observe and count code. ^ Is DTC 16 present? YES -- GO to Drive Test Code 16. NO -- If Code 8, GO to 8.6. See: Code 8/8.6 - Pinpoint Test Status If different code, GO to pinpoint test for corresponding code. See: Trouble Code Descriptions

8.6 - Pinpoint Test Status

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^ Have all prior pinpoint tests been completed? YES -- Go to 8.7. See: Code 8/8.7 - Verify Integrity of Vehicle Wiring NO -- Return to last pinpoint test completed.

8.7 - Verify Integrity of Vehicle Wiring NOTE: If the previous pinpoint steps have been completed, the most likely cause of the concern is wiring related.

Connector Diagram ^ Refer to Pinpoint Test ID, Intermittent Diagnosis Procedure and perform for all affected circuits as shown on this pinpoint test system schematic. See: Component Tests ^ Is resolution achieved? YES -- Stop. Repair is complete, go to drive test code 16. NO -- Go to 8.4. See: Code 8/8.4 - Make Sure All Steps Are Completed

System Pre Check

Connector Diagram

DESCRIPTION Code 9 is generated by the anti-lock electronic control module's detection of high speed sensor resistance. The anti-lock electronic control module will consider the speed sensor circuit to have a high resistance when it exceeds approximately 3 k Ohms. The code may also be generated by a failed internal anti-lock electronic control module circuit.

POSSIBLE CONTRIBUTING BASE BRAKE COMPONENT/VEHICLE WIRING CONCERNS ^ Terminal backout in the anti-lock electronic control module harness connector at Pin 3 or Pin 10 ^ Terminal backout in the RABS speed sensor harness connector at Pins A or B ^ Module or RABS speed sensor connector not fully mated with component ^ Open or intermittent open circuit in Circuits 519 (LG/BK) or 523 (R/PK)

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NOTE: Use Rotunda(r) 73 Digital Multimeter 105-00051 or equivalent for electrical tests.

9.1 - Verify Integrity of Module Connection ^ Turn ignition OFF. ^ Disconnect battery ground cable. ^ Remove the anti-lock electronic control module connector. ^ Pull gently on Circuit 519 (LG/BK) just behind Pin 10 on the harness connector. ^ Pull gently on Circuit 523 (R/PK) just behind Pin 3 on the harness connector. ^ Is terminal fully engaged? YES -- Leave anti-lock electronic control module connector disconnected. Go to 9.2. See: Code 9/9.2 - Verify Integrity of Sensor Connection NO -- Service terminal or connector as needed. Go to 9.6. See: Code 9/9.6 - Clear Code/Pull Code

9.2 - Verify Integrity of Sensor Connection ^ Remove speed sensor connector. ^ Inspect speed sensor component connector for contamination or loose terminals. ^ Gently pull on Circuit 519 (LG/BK) behind Pin B of harness connector. ^ Gently pull on Circuit 523 (R/PK) behind Pin A of harness connector. ^ Are terminals clean and secure? YES -- Leave speed sensor connector disconnected. Go to 9.3. See: Code 9/9.3 - Check For Continuity Along Harness Circuits and 523 NO -- Service terminal or connectors as needed, if not serviceable, replace RABS speed sensor. Go to 9.6. See: Code 9/9.6 - Clear Code/Pull Code

9.3 - Check For Continuity Along Harness Circuits and 523 ^ Set multimeter on 200-ohm scale. ^ Measure resistance between anti-lock electronic control module harness connector Pin 3 and speed sensor harness connector Pin B. ^ Measure resistance between anti-lock electronic control module harness connector Pin 10 and speed sensor harness connector Pin A. ^ Is resistance less than 10 ohms? YES -- Circuit is not open. Go to 9.4. See: Code 9/9.4 - Check For Open Sensor NO -- Find and repair open circuit along circuit 519 (LG/BK) and 523 (R/PK). Go to 9.6. See: Code 9/9.6 - Clear Code/Pull Code

9.4 - Check For Open Sensor ^ Verify multimeter is on 20k Ohm scale. ^ Measure resistance between RABS speed sensor Pins A and B. ^ Is resistance less than 2500 ohms? YES -- Go to 9.5. NO -- Replace RABS speed sensor. Go to 9.6.

9.5 - Make Sure All Steps Are Completed ^ This step requires that a valid diagnostic trouble code has been obtained, all prior diagnostic steps have been completed, and the affected wiring

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integrity has been verified. NOTE: If the above is not complete, chances are that replacement of this or any other system component without specific direction will not, in most circumstances, resolve the concern and will consequently result in customer dissatisfaction. ^ Have all prior diagnostic steps been completed as described above? YES -- Replace anti-lock electronic control unit. Go to Step 9.6. See: Code 9/9.6 - Clear Code/Pull Code YES -- If anti-lock electronic control unit has been replaced and no resolution has been reached, Replace rear axle sensor. Go to Step 9.6. See: Code 9/9.6 - Clear Code/Pull Code NO -- Go to diagnostic step last completed.

9.6 - Clear Code/Pull Code ^ Turn ignition OFF. NOTE: When the battery ground cable has been disconnected and reconnected, some abnormal drive symptoms may occur while the powertrain control module relearns its adaptive strategy. The vehicle may need to be driven 16 km (10 miles) or more to relearn the strategy. ^ Reconnect battery ground cable. ^ Verify all connectors are installed. ^ Locate and disconnect the diagnostic connector from its mating half (Circuits 571 [BK/O] and 483 [R]). ^ Turn ignition ON. ^ Begin diagnostic trouble code flashout by connecting Circuit 571 (BK/O) to a chassis ground for at least 1 second. ^ Observe and count code. ^ Is DTC 16 present? YES -- Go to Drive Test Code 16. NO -- If Code 9, GO to 9.7. See: Code 9/9.7 - Pinpoint Test Status If different code, go to pinpoint test for corresponding code.

9.7 - Pinpoint Test Status ^ Have all prior pinpoint tests been completed? YES -- Go to 9.8. See: Code 9/9.8 - Verify Integrity of Vehicle Wiring NO -- Return to last pinpoint test completed.

9.8 - Verify Integrity of Vehicle Wiring NOTE: If the previous pinpoint test steps have been completed, the most likely cause of the concern is wiring related.

Connector Diagram

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^ Refer to Pinpoint Test ID, Intermittent Diagnosis Procedure and perform for all affected circuits as shown on this pinpoint test system schematic. See: Component Tests ^ Is resolution achieved? YES -- Stop. Repair is complete, go to drive test code 16. NO -- Go to 9.5. See: Code 9/9.5 - Make Sure All Steps Are Completed

System Pre Check

Connector Diagram

DESCRIPTION Code 10 is generated by the anti-lock electronic control module's detection of low speed sensor resistance. The code may also be generated by a short circuit in the Circuits 519 (LG/BK) or 523 (R/PK), or a failed internal anti-lock electronic control module circuit.

POSSIBLE CONTRIBUTING BASE BRAKE COMPONENT/VEHICLE WIRING CONCERNS ^ ^ ^ ^

Short between anti-lock electronic control module harness connector Pin 3 and Pin 10 Short between RABS speed sensor connector Pins A and B Bulkhead connector (between engine compartment and instrument panel) speed sensor terminals shorted together Intermittent short circuit in Circuits 519 (LG/BK) or 523 (R/PK) NOTE: Use Rotunda(r) 73 Digital Multimeter 105-00051 or equivalent for electrical tests.

10.1 - Verify Integrity of Module Connection ^ Turn ignition OFF. ^ Disconnect battery ground cable. ^ Remove the anti-lock electronic control module connector. ^ Pull gently on wire just behind Pin 3 on the harness connector. ^ Pull gently on wire just behind Pin 10 on the harness connector. ^ Is terminal fully engaged? YES -- Leave anti-lock electronic control module connector disconnected. Go to 10.2. See: Code 10/10.2 - Verify Integrity of Sensor Connection NO -- Service terminal or connector as needed. Go to 10.7. See: Code 10/10.7 - Clear Code/Pull Code

10.2 - Verify Integrity of Sensor Connection ^ Remove speed sensor connector.

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^ Inspect speed sensor component connector. ^ Gently pull on wire behind Pin B of harness connector. ^ Gently pull on wire behind Pin A of harness connector. ^ Are all connections clean and secure? YES -- Leave speed sensor connector disconnected. Go to 10.3. See: Code 10/10.3 - Check For Short In Harness Circuit 519 With Circuit 523 NO -- Terminal(s) in component connector are loose, bent, deformed, or corroded. Service terminal or connectors as needed, if not serviceable, replace speed sensor. Go to 10.7. See: Code 10/10.7 - Clear Code/Pull Code NO -- Terminal(s) in harness connector move back or come free of connector. Service terminal or connector as needed. Go to 10.7. See: Code 10/10.7 - Clear Code/Pull Code

10.3 - Check For Short In Harness Circuit 519 With Circuit 523 ^ Set multimeter on 20k Ohm scale. ^ Verify speed sensor connector is disconnected. ^ Measure resistance between anti-lock electronic control module harness connector Pin 3 and Pin 10. ^ Is resistance greater than 20k Ohms? YES -- Circuits are not shorted. GO to 10.4. See: Code 10/10.4 - Check For Short to Chassis GRND Along Circuit 523 NO -- Find and repair short along Circuits 519 (LG/BK) and 523 (R/PK). GO to 10.7. See: Code 10/10.7 - Clear Code/Pull Code

10.4 - Check For Short to Chassis GRND Along Circuit 523 ^ Verify multimeter is on 20k Ohm scale. ^ Measure resistance between anti-lock electronic control module harness connector Pin 10 and chassis ground. ^ Is resistance greater than 20k Ohms? YES -- Circuit is not shorted. Go to 10.5. See: Code 10/10.5 - Check For Shorted Speed Sensor NO -- Find and repair short circuit along circuit 523 (R/PK). Go to 10.7. See: Code 10/10.7 - Clear Code/Pull Code

10.5 - Check For Shorted Speed Sensor ^ Verify multimeter is on 20k Ohm scale. ^ Measure resistance between RABS speed sensor Pins A and B. ^ Is resistance steady and 900-2500 ohms? YES -- Go to 10.6. See: Code 10/10.6 - Make Sure All Steps Are Completed NO -- Replace speed sensor. Go to 10.7. See: Code 10/10.7 - Clear Code/Pull Code

10.6 - Make Sure All Steps Are Completed ^ This step requires that a valid diagnostic trouble code has been obtained, all prior diagnostic steps have been completed, and the affected wiring integrity has been verified. NOTE: Make sure to complete all steps. Failure to do so could cause replacement of good parts. ^ Have all prior diagnostic steps been completed as described above? YES -- Replace anti-lock electronic control module. Go to step 10.7. See: Code 10/10.7 - Clear Code/Pull Code YES -- If anti-lock electronic control module has been replaced and no resolution has been reached, replace rear axle speed sensor. Go to

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step 10.7. See: Code 10/10.7 - Clear Code/Pull Code NO -- Go to diagnostic step last completed and continue.

10.7 - Clear Code/Pull Code NOTE: When the battery ground cable has been disconnected and reconnected, some abnormal drive symptoms may occur while the powertrain control module relearns its adaptive strategy. The vehicle may need to be driven 16 km (10 miles) or more to relearn the strategy. ^ Turn ignition OFF. ^ Reconnect battery ground cable. ^ Verify all connectors are installed. ^ Locate and disconnect the diagnostic connector from its mating half (Circuits 571 [BK/O] and 483 [R]). ^ Turn ignition ON. ^ Begin diagnostic trouble code flashout by connecting Circuit 571 (BK/O) to a chassis ground for at least 1 second. ^ Observe and count code. ^ Is Code 16 set? YES -- Go to drive test code 16. NO -- If code 10, go to 10.8. See: Code 10/10.8 - Pinpoint Test Status If different code, go to pinpoint test for corresponding code.

10.8 - Pinpoint Test Status ^ Have all prior pinpoint tests been completed? YES -- Go to 10.9. See: Code 10/10.9 - Verify Integrity of Vehicle Wiring NO -- Return to last pinpoint test completed.

10.9 - Verify Integrity of Vehicle Wiring If the previous pinpoint test steps have been completed, the most likely cause of the concern is wiring related.

Connector Diagram ^ Refer to Pinpoint Test ID, Intermittent Diagnosis Procedure and perform for all affected circuits as shown on this pinpoint test system schematic. See: Component Tests ^ Is resolution achieved? YES -- Stop. Repair is complete go to drive test code 16. NO -- Go to 10.6. See: Code 10/10.6 - Make Sure All Steps Are Completed

System Pre Check

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Schematic DESCRIPTION Code 11 is caused by the stoplight switch (13480) being closed prior to the vehicle moving. If the stoplight switch remains closed when the vehicle begins to move, the REAR ABS warning light will turn on at approximately 26 km/h (16 mph). Code 11 will not be latched in the anti-lock electronic control modules memory until the speed of the vehicle exceeds 60 km/h (37 mph) for at least 10 seconds. If the vehicle does not exceed 60 km/h (37 mph) for at least 10 seconds, then the REAR ABS warning light will turn on but the anti-lock electronic control module will not latch a code. Code 11 can be caused by a driver who is resting his or her foot on the brake pedal with just enough pressure to close the stoplight switch, while driving at least 60 km/h (37 mph) for a minimum of 10 seconds. When this occurs, a Code 11 will be latched by the anti-lock electronic control module. POSSIBLE CONTRIBUTING BASE BRAKE COMPONENT/VEHICLE WIRING CONCERNS ^ Terminal backout in the anti-lock electronic control module harness connector at Pin 11 ^ Missing (burned-out) stoplight bulbs. All stoplight bulbs must be missing or burned-out to cause a Code 11 ^ An intermittent/continuous open in Circuit 810 (R/LG) for Aerostar or 511 (LG) for Ranger. This open would be between module connector Pin 11 and the stoplight switch ^ Worn or damaged stoplight switch NOTE: Use Rotunda(r) 73 Digital Multimeter 105-00051 or equivalent for electrical tests.

11.1 - Check Vehicle Stoplight Operation ^ Turn ignition to the OFF position. ^ Apply pressure to the brake pedal and then release pressure while observing the stoplights. ^ Do lights work properly? YES -- Go to 11.4. See: Code 11/11.4 - Check Continuity Module Pin 11 and the Stoplight Switch NO -- Lights do not illuminate. Go to 11.2. See: Code 11/11.2 - Check Vehicle Stoplights NO -- Lights always illuminated. Repair or replace stoplight switch. Go to 11.6. See: Code 11/11.6 - Clear Code/Pull Code

11.2 - Check Vehicle Stoplights NOTE: Both stoplight bulbs need to be burned out to cause a Code 11. ^ Check vehicle stoplight bulbs. ^ Are the stoplight bulbs burned out? YES -- Replace stoplight bulbs and go to 11.6. See: Code 11/11.6 - Clear Code/Pull Code NO -- Go to 11.3. See: Code 11/11.3 - Check For Blown Stoplight Fuse

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11.3 - Check For Blown Stoplight Fuse ^ Remove and visually inspect stoplight fuse located in the fuse panel. ^ Is the fuse blown? YES -- Replace fuse and investigate reason for blown fuse. Go to 11.6. See: Code 11/11.6 - Clear Code/Pull Code NO -- Check circuit 511 (LG) for open condition. If none found, then repair or replace stoplight switch. Go to 11.6. See: Code 11/11.6 Clear Code/Pull Code

11.4 - Check Continuity Module Pin 11 and the Stoplight Switch ^ Set multimeter on 20-volt scale. ^ Step on brake pedal. ^ Measure voltage between module connector Pin 11 and chassis ground. ^ Is the voltage greater than 9 volts? YES -- Reinstall all connectors. NO -- Voltage is less than 2 volts. Find and repair open circuit between anti-lock electronic control module connector (Pin 11), and stoplight switch. Reinstall all connectors. Go to 11.5. See: Code 11/11.5 - Make Sure All Steps Are Completed

11.5 - Make Sure All Steps Are Completed ^ This step requires that a valid diagnostic trouble code has been obtained, all prior diagnostic steps have been completed, and the affected wiring integrity has been verified. NOTE: Make sure to complete all steps. Failure to do so could cause replacement of good components. ^ Have all prior diagnostic steps been completed as described above? YES -- Replace anti-lock electronic control module. Go to 11.6. See: Code 11/11.6 - Clear Code/Pull Code YES -- If anti-lock electronic control module has been replaced and no resolution has been reached, replace stoplight switch. Go to 11.6. See: Code 11/11.6 - Clear Code/Pull Code NO -- Go to diagnostic step last completed and continue.

11.6 - Clear Code/Pull Code NOTE: When the battery ground cable has been disconnected and reconnected, some abnormal drive symptoms may occur while the powertrain control module relearns its adaptive strategy. The vehicle may need to be driven 16 km (10 miles) or more to relearn the strategy. ^ Turn ignition OFF. ^ Reconnect battery ground cable. ^ Verify all connectors are installed. ^ Locate and disconnect the diagnostic connector from its mating half (Circuits 571 [BK/O] and 483 [R]). ^ Turn ignition switch (11572) ON. ^ Begin diagnostic trouble code flashout by connecting Circuit 571 (BK/O) to a chassis ground for at least 1 second. ^ Observe and count code. ^ Is Code 16 set? YES -- GO to drive test code 16. NO -- If Code 11, GO to 11.7. See: Code 11/11.7 - Pinpoint Test Status If different code, go to pinpoint test for corresponding code.

11.7 - Pinpoint Test Status

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^ Have all pinpoint tests been completed? YES -- Go to drive test code 16. NO -- Return to last pinpoint test completed.

System Pre Check

Connector Diagram

DESCRIPTION Code 12 is generated when the anti-lock electronic control module detects that the brake fluid level in the brake master cylinder reservoir (2K478) is low for one or more seconds. It can also be generated by a short in the stoplight circuit.

POSSIBLE CONTRIBUTING BASE BRAKE COMPONENT/VEHICLE WIRING CONCERNS ^ Low brake master cylinder fill level ^ Brake fluid leaks in vehicle brake system ^ Worn or damaged master cylinder brake fluid level switch, or brake fluid level circuit shorted to ground ^ Brake master cylinder reservoir float that sticks in the bottom of brake master cylinder reservoir or does not float ^ Failed diode-resistor element in stoplight circuit ^ Damaged ignition switch ^ Ground short in Circuits 512 (T/LG) or 531 (DG/Y) ^ Damaged anti-lock electronic control module NOTE: Use Rotunda(r) 73 Digital Multimeter 105-00051 or equivalent for electrical tests.

12.1 - Check Warning Lights

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Connector Diagram ^ Key OFF. ^ Locate and disconnect the diagnostic connector from its mating half (Circuits 571 [BK/O] and 483 [R]). ^ Reconnect diagnostic connector. ^ Key ON. ^ Do both the red brake and yellow RABS lamps come on? YES -- Hard fault. Go to 12.2. See: Code 12/12.2 - Check Brake Fluid Level In Master Cylinder NO -- If the brakes have been serviced recently, or if brake fluid has been added to the system recently, most likely, the Code 12 was falsely set at that time and the RABS is OK. If this is not the case, go to Pinpoint Test ID for Intermittent Diagnosis Procedures for the affected circuits. See: Component Tests NO -- Refer to the system schematic for this pinpoint test. If yellow RABS lamp is ON and Code 12 is present, service open circuit on pin 2, circuit 512 (T/LG).

12.2 - Check Brake Fluid Level In Master Cylinder ^ Key OFF. ^ Check the brake fluid level in the brake master cylinder reservoir. ^ Is the fluid level within specification? YES -- Go to 12.3. See: Code 12/12.3 - Verify Float Buoyancy NO -- Check for leaks in the brake system. Repair as required. Fill brake master cylinder reservoir to the required level. GO to 12.9. See: Code 12/12.9 - Clear Code/Pull Code

12.3 - Verify Float Buoyancy ^ Remove the brake master cylinder filler cap. ^ Attempt to push down the float with a clean, blunt steel implement, then let it float back up. ^ Does the float go down then float back up? YES -- Go to 12.4. See: Code 12/12.4 - Check Circuit 531 (DG/Y) For Ground Short NO -- The float stays on the bottom of the brake master cylinder reservoir. Replace the brake master cylinder reservoir. Bleed the brake system. Go to 12.9. See: Code 12/12.9 - Clear Code/Pull Code

12.4 - Check Circuit 531 (DG/Y) For Ground Short ^ Key OFF. ^ Disconnect brake fluid level switch harness connector. ^ Disengage parking brake. ^ Check for ground short on Circuit 531 (DG/Y) at brake fluid level switch harness connector. ^ Is there a ground short? YES -- Repair ground short in circuit 531 (DG/Y). Reconnect all components. Go to 12.9. See: Code 12/12.9 - Clear Code/Pull Code NO -- Go to 12.5. See: Code 12/12.5 - Check Diode/Resistor Element

12.5 - Check Diode/Resistor Element ^ Engage parking brake. ^ Check for ground short on Circuit 531 (DG/Y) at brake fluid level switch harness connector.

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^ Is there a ground short? YES -- Replace resistor/diode element. Reconnect all components. Go to 12.9. See: Code 12/12.9 - Clear Code/Pull Code NO -- Go to 12.6. See: Code 12/12.6 - Check Circuit 512 (T/Lg) For Ground Short

12.6 - Check Circuit 512 (T/Lg) For Ground Short ^ Key OFF. ^ Disconnect battery ground cable. ^ Disconnect fluid level switch. ^ Disconnect ignition switch. ^ Disconnect anti-lock electronic control module. ^ Check for short to ground on Pin 2 of anti-lock electronic control module harness connector (Circuit 512 [T/LG]). ^ Is there a ground short? YES -- Repair ground short in Circuit 512 (T/LG). Reconnect all components. Go to 12.9. See: Code 12/12.9 - Clear Code/Pull Code NO -- GO to 12.7. See: Code 12/12.7 - Check Ignition Switch

12.7 - Check Ignition Switch ^ Reconnect ignition switch. ^ Check for short to ground on Pin 2 of anti-lock electronic control module harness connector (Circuit 512 [T/LG]). ^ Is there a ground short? YES -- Replace ignition switch. Reconnect all components. Go to 12.9. See: Code 12/12.9 - Clear Code/Pull Code NO -- Go to 12.8. See: Code 12/12.8 - Check Brake Fluid Level Switch

12.8 - Check Brake Fluid Level Switch ^ Reconnect brake fluid level switch. ^ Check for short to ground on Pin 2 of anti-lock electronic control module harness connector (Circuit 512 [T/LG]). ^ Is there a ground short? YES -- Replace brake fluid level switch. Reconnect all components. Go to 12.9. See: Code 12/12.9 - Clear Code/Pull Code NO -- Replace anti-lock electronic control module. Go to 12.9. See: Code 12/12.9 - Clear Code/Pull Code

12.9 - Clear Code/Pull Code NOTE: When the battery ground cable has been disconnected and reconnected, some abnormal drive symptoms may occur while the powertrain control module relearns its adaptive strategy. The vehicle may need to be driven 16 km (10 miles) or more to relearn the strategy. ^ Key OFF. ^ Verify all connectors are installed. ^ Locate and disconnect the diagnostic connector from its mating half (Circuits 571 [BK/O] and 483 [R]). ^ Key ON. ^ Begin diagnostic trouble code flashout by grounding Circuit 571 (BK/O) for 1 second. ^ Was DTC 16 or 12 retrieved?

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YES -- DTC 16. Go to pinpoint test DT4. YES -- DTC 12. If all steps are complete, go to pinpoint test ID. See: Component Tests If all steps are not complete, return to the last step completed and continue. NO -- A different code. Go to pinpoint test for corresponding DTC. See: Component Tests

Code 13 DESCRIPTION Code 13 is generated when a fault is found with the anti-lock electronic control unit. The Anti-lock Electronic Control Unit must be replaced and Test Drive Code 16 must be performed.