Climate Control
316 HO 163 Climate Control WJB (10-25-01)
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These technical training materials are current as of the date noted on the materials, and may be revised or updated without notice. Always check for revised or updated information. To help avoid personal injury to you or others, and to avoid damage to the vehicle on which you are working, you must always refer to the latest Mercedes- Benz Technical Publication and follow all pertinent instructions when testing, diagnosing or making repair. Illustrations and descriptions in this training reference are based on preliminary information and may not correspond to the final US version vehicles. Refer to the official introduction manual and WIS when available. Copyright Mercedes- Benz USA, LLC, 2001
Reproduction by any means or by any information storage and retrieval system or translation in whole or part is not permitted without written authorization from Mercedes- Benz USA, LLC or its successors. Published by Mercedes- Benz USA, LLC Printed in U. S.A. 2
New for the 2002 M-Class • Compressor with almost doubled capacity • AC controls with LED indication • Rear blower control unit with controls for air direction and speed
• Additional rear vents 3
AAC Pushbutton Control Module (N22)
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Blower Control Ring • Left control ring is used to select 11 manuals speeds • The upper button selects front defrost • The lower button selects the recirculation mode • To turn the system off turn the fan dial to “ O “.
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Temperature Control Ring • Center Control Ring is used to select the desired temperature • Desired temperature can be set in the “AUTO” mode • The upper button can be used to program the “Auto” temperature • The lower button is used to shut off the compressor and to select the “Rest” mode 6
Air Distribution Control Ring • The right control ring is used to select the front manual air distribution • The upper button activates the rear defroster • The lower button is used to turn off rear unit
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Rear Blower Control Unit
• The left climate control button selects the rear fan speed • The right button selects air distribution • The center ”Auto” button allows the front control panel to select the fan speed and air distribution
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Air Distribution
Cooling Mode
Heating Mode
Blend mode 9
Air Distribution Groups Main HVAC unit
Upper Instrument Panel Ducting
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Rear Blower Unit Ducting
Consists of: • Ducting • Rear blower motor • Rear blower motor regulator • Rear temperature sensor B10/7 • Rear air flap motor M2/21
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AAC Circuit Inputs B10/6
Temperature sensors B10/6 - Evap sensor
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AAC Circuit Inputs B10/6
B10/7
Temperature sensors B10/6 - Evap sensor B10/7 - Rear temp sensor
B10/7
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AAC Circuit Inputs B10/6
B10/24 B10/7
Temperature sensors B10/6 - Evap sensor B10/7 - Rear temp sensor
B10/7
B10/24 - Center nozzle temp sensor
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AAC Circuit Inputs B10/6
B10/24
B10/25
B10/7
Temperature sensors B10/6 - Evap sensor B10/7 - Rear temp sensor
B10/7
B10/24 - Center nozzle temp sensor B10/25 - Front footwell temp sensor
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AAC Circuit Inputs B10/6
B10/24 B10/25
B10/7
B32
Temperature sensors B10/6 - Evap sensor B10/7 - Rear temp sensor
B10/7
B10/24 - Center nozzle temp sensor B10/25 - Front footwell temp sensor B32 - Sun sensor
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AAC Circuit Inputs B10/6
B10/24 B10/25
B10/7
B32
Temperature sensors B10/6 - Evap sensor B10/7 - Rear temp sensor B10/24 - Center nozzle temp sensor
B14 - Ambient temp sensor B10/7
B10/25 - Front footwell temp sensor B32 - Sun sensor
N22b1- In-car Temp N72/2 - Rear control sensor field module N72 - Lower Control Panel B12/2 - Refrigerant pressure/temperature sensor
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AAC Outputs M13
M2/2
• A9 - Compressor • N29/2 - Rear Blower regulator • A32 Recircultated air unit • Electric actuators M2/5, 2/6, 2/8, 2/12, 2/15, 2/21 • M13 - Auxiliary water pump • M2/2 - Module box blower motor
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Electric Actuators The electric actuators are the same as those used on the 203 chassis
B+ Control
Coding pins
Ground 19
Compressor Control
A1 - Instrument cluster A9 - Compressor B10/6 - Evaporator sensor
B12/2 - Refrigerant pressure/temperature sensor B14 - Outside temperature sensor N22 - AAC pushbutton module 20
Cooling Fan Control
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Acronyms/ abbreviations used in this program: AC - Air Conditioning A1 - Instrument Cluster A9 - AC compressor A32 - Recirculation air unit B10/6 - Evaporator temperature sensor B10/7 - Rear temperature sensor B10/24 - Center nozzle temperature sensor B10/25 - Front footwell temperature sensor B12/2 - Refrigerant pressure/temperature sensor B14 - Outside temperature sensor B32 - Sun sensor EVAP - evaporator HVAC - Heat, Ventilation, Air Conditioning LED - Light emitting diode M’s - Motors N22 - AC pushbutton control unit N22b1 - In car temperature sensor N29/2 - Rear blower regulator
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