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Air Conditioning - Diagnostics: Other Porsche Cayenne I

Automatic HVAC System 6 illustrations ~5395 words

Distinguishing characteristics

The various air-conditioning systems can be distinguished from one another via the diagnosis software number in the PST 2 menu option 'Identification' as follows.

  1. The diagnosis software number 01xx stands for 2-zone air-conditioning.
  2. The diagnosis software number 02xx stands for 4-zone air-conditioning.
  3. The diagnosis software number 03xx stands for manual air-conditioning.

The 3rd and 4th characters identify the software version for the corresponding air-conditioning system.

General instructions/safety instructions

CAUTIONDanger of damage due to improper handling of batteries and control module plug connections! Disconnect the battery connection terminals only when the engine is switched off! Start the engine only when the battery connection terminals are properly connected! Pull off or push on plug connections for the control units or other electronic components only when the ignition is switched off! Disconnect the negative terminal of the battery before welding work on the vehicle.
WARNINGDanger of injury as a result of contact with liquid or gaseous refrigerants! Wear suitable protective gloves to protect your hands! Treat affected skin in the same way as in the case of freezing. Rinse immediately with cold water and then consult a physician! Wear safety goggles to protect your eyes! If refrigerant still gets in your eyes, consult a physician immediately! When working on the refrigerant circuit, always read the related introductions and warnings! Safety regulations for working on air-conditioned vehicles and dealing with refrigerant R 134a, refer to the WARNING below. Safety regulations for working with extraction and filling systems, refer to the WARNING below.
WARNINGRisk of injury! Do not smoke! Refrigerants could decompose in the burning ash. The resulting substances are toxic and should not be breathed in. The leaking refrigerant is not only colorless and odorless, but is also heavier than air and therefore displaces oxygen. If refrigerant gas escapes despite all safety measures having been taken, there is an undetectable risk of suffocation in poorly ventilated rooms and erection pits. The gas/air mixture formed when refrigerant escapes should not be breathed in but rather extracted via suitable extraction systems (workshop extraction system). No welding, soldering or hard-soldering should be carried out on any part of the filled air-conditioning system. This also applies to welding and soldering work on the vehicle when there is a danger of parts of the air-conditioning system heating up. The warming causes very strong overpressure in the system, which can destroy components of the air-conditioning system.

Note. Communication with the air-conditioning system regulator control module can only be established once the ignition is switched on. The fault memory of the air-conditioning system regulator control module must be read out before troubleshooting.

Possible causes of fault

Note. The 'possible causes of fault that are responsible for the fault are listed here. Please note that in certain circumstances further faults can be stored in the fault memory after troubleshooting (e.g. if plugs are disconnected). After carrying out repairs, read out the fault memory of all control modules and erase any faults.

Fault type

The following fault types are possible

  1. No display
  2. Upper limit value exceeded
  3. Lower limit value not reached
  4. Mechanical fault
  5. No signal/communication
  6. No or incorrect basic setting/adaptation
  7. Short circuit to B+
  8. Short circuit to ground
  9. Implausible signal
  10. Open circuit/short circuit to ground
  11. Open circuit/short circuit to B+
  12. Electrical fault in electric circuit
  13. Please read out fault memory
  14. Faulty

Fault status

The following status types are possible

  1. present
  2. not present

This information should be saved using the Save key [F4] and printed out.

Note. Visual inspection: During troubleshooting, please check first that the affected pins on the plug connection of the air-conditioning system regulator control module are neither damaged nor corroded. The wiring and plugs of the affected components must also be checked for external damage and correct contacts. Repair damaged or corroded pins if possible, otherwise replace affected pins. Repair or replace damaged wires.

Note. Battery voltage: A battery voltage of between 11.4 and 14.5 V is required for troubleshooting. This must be checked and provided if necessary. Voltages as well as components or fuses (input side) must be guaranteed on the vehicle electrical system.

Tools

WARNINGDanger of injury when driving and working on the vehicle! Never hang the 9588 Porsche System Tester II over the steering wheel! Always place tools and special tools outside the functioning range of all airbags!

Note. Plug contacts are optimally designed to suit the plug system! Operations on pins can cause contact problems! Always use suitable measurement tools, adapter plugs and test cables.

Scheme 523

Scheme 523: Commercially available battery charger
Scheme 523: Commercially available battery charger

Scheme 524

Scheme 524: 9588 Porsche System Tester II
Scheme 524: 9588 Porsche System Tester II

Scheme 525

Scheme 525: Commercially available digital multimeter
Scheme 525: Commercially available digital multimeter

Scheme 526

Scheme 526: 9684 Measurement tool set
Scheme 526: 9684 Measurement tool set

Socket A (black), 24-pin (2-zone and 4-zone air conditioning)

PinDesignationPinDesignation
1Passenger blower (servo motor for left central vents)2Defrost flap (servo motor, feedback signal lead)
3Fresh-air/recirculation valve (servo motor, feedback signal lead)4Air intake temperature sensor (Air intake temperature sensor)
5Outlet temperature sensor (front right)6Outlet temperature sensor (front right footwell)
7Outlet temperature sensor (front left footwell)8Left temp, valve (left servo motor)
9Passenger blower (servo motor for left central vents)10Temp, sensor signal (evaporator temperature sensor)
11Footwell flap (left servo motor, feedback signal lead)12Right temp, valve (right servo motor, feedback signal lead)
13Left temp, valve (left servo motor, feedback signal lead)14Passenger blower (servo motor for left central vents, feedback signal lead)
15Outlet temperature sensor (front left)16Left temp, valve (left servo motor)
17Fresh-air/recirculation valve (servo motor for fresh-air/recirculation valve)18Fresh-air/recirculation valve (servo motor for fresh-air/recirculation valve)
19Right temp, valve (right servo motor)20Right temp, valve (right servo motor)
21Footwell flap (left servo motor)22Footwell flap (left servo motor)
23Passenger blower (servo motor for left side vents)24Passenger blower (servo motor for left side vents)

CONNECTOR PIN TERMINAL REFERENCE CHART

Socket A, (black) 24-pin (manual air conditioning)

PinDesignationPinDesignation
1Defrost flap servo motor2Not used
3Not used4Not used
5Not used6Not used
7Not used8Servo motor for temperature valve
9Defrost flap servo motor10Not used
11Footwell flap servo motor (feedback signal footwell flap)12Recirculation valve servo motor (feedback signal recirculation valve)
13Servo motor for temperature valve (feedback signal temperature valve)14Servo motor for passenger blower (feedback signal passenger blower)
15Not used16Temperature valve servo motor
17Power supply (AUX)18Water pump relay
19Recirculation valve servo motor20Recirculation valve servo motor
21Footwell flap servo motor22Footwell flap servo motor
23Servo motor for passenger blower24Servo motor for passenger blower

CONNECTOR PIN TERMINAL REFERENCE CHART

Socket B, (red) 24-pin (4-zone air conditioning)

PinDesignationPinDesignation
1Passenger blower (servo motor for right side vents)2Not used
3Not used4Not used
5Passenger blower (servo motor for right side vents, feedback signal lead)6Not used
7Not used8Not used
9Passenger blower (servo motor for right side vents)10Passenger blower (servo motor for right central vents, feedback signal lead)
11Not used12Not used
13Not used14Footwell flap (right servo motor, feedback signal lead)
15Not used16Not used
17Passenger blower (servo motor for right central vents)18Passenger blower (servo motor for right central vents)
19Footwell flap (right servo motor)20Footwell flap (right servo motor)
21Not used22Not used
23Not used24Not used

CONNECTOR PIN TERMINAL REFERENCE CHART

Socket C (yellow), 24-pin (2-zone and 4-zone air conditioning)

PinDesignationPinDesignation
1Not used2Not used
3Not used4Not used
5Passenger blower (servo motor for left side vents, feedback signal lead)6Defrost flap (defrost flap servo motor)
7Left sun sensor signal8Power supply (front blower regulator)
9Not used10Not used
11Windscreen heating Not used12Feedback voltage (front blower regulator)
13Not used14Auxiliary heater (Water pump activation)
15Right sun sensor signal16AUX Not used
17CAN high (CAN comfort high)18CAN low (CAN comfort low)
19Air quality sensor20Not used
21Refrigerant temp, sensor not used22Not used
23Pressure sensor24Defrost flap (defrost flap servo motor)

CONNECTOR PIN TERMINAL REFERENCE CHART

Socket C, (yellow) 24-pin (manual air conditioning)

PinDesignationPinDesignation
1Not used2Not used
3Not used4Not used
5Not used6Not used
7Not used8Not used
9Not used10Not used
11Not used12Fan diagnosis (Feedback signal from blower regulator)
13Defrost flap servo motor14Not used
15Defrost flap servo motor (feedback signal lead)16AUX
17CAN comfort high18CAN comfort low
19Not used20Not used
21Evaporator temperature sensor22Not used
23Pressure sensor24Not used

CONNECTOR PIN TERMINAL REFERENCE CHART

Socket E (black), 12-pin (manual, 2-zone and 4-zone air conditioning)

PinDesignationPinDesignation
15 V reference voltage2Blower regulator activation (front blower regulator)
3Not used4Externally-controlled compressor (activation of air-conditioning compressor)
5Terminal 30A6Not used
7Not used8Signal ground
9Terminal 3110Terminal 31
11Externally-controlled compressor (activation of air-conditioning compressor)12Ground sensor

CONNECTOR PIN TERMINAL REFERENCE CHART

Scheme 527

Scheme 527: Rear connector assignment
Scheme 527: Rear connector assignment

Socket B, (red) 20-pin (4-zone air conditioning)

PinDesignationPinDesignation
1Power supply (rear blower regulator)2Air flow flap (rear left servo motor)
3Air flow flap (rear right servo motor)4Air flow flap (rear left servo motor)
5Air flow flap (rear right servo motor)6Not used
7Left B-pillar flap (rear left servo motor)8Right B-pillar flap (rear right servo motor)
9Passenger blower (rear left tunnel)10Right B-pillar flap (rear right servo motor)
11Not used12Right temp, valve (rear right servo motor)
13Right temp, valve (rear right servo motor)14Left temp, valve (rear left servo motor)
15Left temp, valve (rear left servo motor)16Passenger blower (rear right tunnel)
17Passenger blower (rear right tunnel)18Not used
19Not used20Not used

CONNECTOR PIN TERMINAL REFERENCE CHART

Socket C, (yellow) 16-pin (4-zone air conditioning)

PinDesignationPinDesignation
1Not used2Passenger blower (rear left tunnel)
3Left B-pillar flap (rear left servo motor)4Air flow flap (rear left servo motor, feedback signal lead)
5Left B-pillar flap (rear left servo motor, feedback signal lead)6Right B-pillar flap (rear right servo motor, feedback signal lead)
7Air flow flap (rear right servo motor, feedback signal lead)8Not used
9Not used10Left seat heating (rear left seat heating)
11Right seat heating (rear right seat heating)12Blower regulator (rear blower regulator)
13Passenger blower (rear right tunnel, feedback signal lead)14Left temp, valve (rear left servo motor, feedback signal lead)
15Right temp, valve (rear right servo motor, feedback signal lead)16Passenger blower (rear left tunnel, feedback signal lead)

CONNECTOR PIN TERMINAL REFERENCE CHART

Socket D, (black) 16-pin (4-zone air conditioning)

PinDesignationPinDesignation
1Terminal 30A2Not used
35 V reference voltage4Not used
5Not used6Ground sensor
7Signal ground8CAN high (CAN comfort high)
9Not used10Outlet temperature sensor (rear right)
11Outlet temperature sensor (rear left)12Temp, sensor signal not used
13Feedback voltage (rear blower regulator)14Not used
15Terminal 3116CAN low (CAN comfort low)

CONNECTOR PIN TERMINAL REFERENCE CHART

Required status of recirculation valve

  1. For 2-zone and 4-zone air conditioning systems only!

In the menu item 'Actual values', the current required position of the recirculation valve can be read out. Numbers from '0' to '8' are output. The meaning of each number is shown in the following table.

0100% position 'Fresh air'
10% position 'Recirculation air' set by air quality sensor
20% position 'Recirculation air' set by recirculation button
30% position 'Recirculation air' set by wipe and wash signal
40% position 'Recirculation air' set by 'Pull down' mode (at high outside temperatures)
5Intermediate position 'Partial recirculation air'
60% position 'Recirculation' set by reverse gear (up to two minutes after engine start)
70% position 'Recirculation air' set by air conditioning system regulator at 'OFF'
80% position 'Recirculation air' set by blower position '0'

RECIRCULATION VALVE REFERENCE CHART

Compressor OFF code

In menu item 'Inputs signals', the actual reason for compressor shutdown can be read out. Numbers from '1' to '23' are output. The meaning of each number is shown in the following table.

Note. If the compressor is switched on, the display shows the number '15' or the text 'comp. ON'!

1Refrigerant pressure too high above 32 bar compressor OFF below 26 bar compressor ON again
2Blower at step '0' (actual voltage < 3 V) or blower/blower drive circuit faulty
3Refrigerant pressure too low If outside temperature above 5 °C: below + 1.4 bar compressor OFF above + 2.0 bar compressor ON again If outside temperature below 5 °C: below + 0.5 bar compressor OFF above + 1.0 bar compressor ON again
5Engine runs for < 5 seconds after starting
6'ECON' mode active
7Air-conditioning system 'OFF'
8Outside temperature too low below + 2 °C compressor OFF above + 3.5 °C compressor ON again
10Vehicle voltage too low (< 10.1 V when engine running)
11Engine temperature > 118 °C (does not apply for all versions)
12Shutdown request from engine control module via CAN
13Vehicle voltage too high (> 1 6 V)
14Evaporator temperature too low below -2 °C compressor OFF above 0 °C compressor ON again
15No condition for cutoff exists, the compressor is being activated.
16Fault 'A/C compressor drive circuit'
17Fault 'Pressure sensor'
18Engine speed too high (> 3000 rpm when vehicle stationary (0 km / h )
19Cutoff request from vehicle electrical system control module via CAN
20Refrigerant loss (does not apply for all versions)
23Cutoff due to lack of radiator fan signal (does not apply for all versions)

AIR CONDITION COMPRESSOR REFERENCE CHART

Drive links

In menu item 'Drive links', both a 'self test' (system check) and a test of individual drive links can be performed.

Note. The vehicle engine must not be running! The air conditioning system regulator(s) must not be 'OFF'! The engine coolant should be at operating temperature!

Note. The waiting time until a particular position is set is approx. 5 seconds. Only then can the next step take place!

  1. Manual, 2-zone and 4-zone air conditioning systems!
  2. For the 'self test', the blower(s) is/are first set at 1/2 power. All valves are then driven to the CLOSED position. The blower(s) is/ are then set at full power. Finally, all valves are driven to the OPEN position. The procedure lasts about 20 seconds.
  3. After the 'self test' the individual front valves are checked.
  4. For checking the individual valves, the front blower is set at 3/4 power.
  5. The valve under test is driven to the OPEN and CLOSED stops with a 5-second cycle time.
  6. All other valves are driven to the CLOSED position.
  7. Only the 'passenger blower valve' corresponding to the front 'temperature valves' is driven to the OPEN stop.
  8. After activating the front valves, the front 'blower regulator' is set to steps 1/4, 1/2, full and zero power.
  9. For this procedure, the front 'passenger blower valve' is driven to the OPEN stop, all other valves being driven to the CLOSED stop.
  10. After activating the front 'blower regulator', the 'coolant pump' is activated.
  11. For 4-zone air conditioning system only!
  12. After the 'coolant pump', the individual valves at the rear are checked.
  13. For checking the individual valves, the rear blower is set at 3/4 power.
  14. The valve under test is driven to the OPEN and CLOSED stops with a 5-second cycle time.
  15. All other valves are driven to the CLOSED position.
  16. Only the 'air flow valve' corresponding to the rear 'temperature valves' is driven to the OPEN stop.
  17. For all valves except the two 'B-pillar valves' themselves, the respective 'B-pillar valve' is driven to the B-pillar stop.
  18. After activating the rear valves, the rear 'blower regulator' is set to steps 1/4, 1/2, full and zero power.
  19. For this procedure, the 'air-flow valve' and the right 'B-pillar valve' are driven to the OPEN stop, all other valves being driven to the CLOSED stop.

Note. Before and after the drive link test, the fault memory must be evaluated!

  1. Using the 9588 Porsche System Tester II, select the menu item 'Drive links'.
  2. Switch on air conditioning system(s) and press: button. NOTE: The drive link check can be aborted at any time with the [<<] button! Checking of individual drive links can be terminated at any time with the [F8] 'Stop' button!
  3. Press [F8] 'Start' to begin the drive link check.
  4. Press [F8] 'Start' once more to perform the 'self test' of the air-conditioning system regulator. NOTE: The procedure lasts about 20 seconds and ends automatically. All subsequent drive link activations must be terminated with the [F8] 'Stop' button!
  5. Press the [F8] 'Start' button again to activate the next drive link of the air-conditioning system regulator.
  6. When the drive link test has run fully through, press the [F8] 'Start' button to repeat it or the [<<] button to end.

Coding

In menu point 'Coding', either 'heat-absorbing glazing' or 'standard glazing' can be coded to suit the vehicle!

Note. The vehicle engine must not be running! The air conditioning system regulator(s) must not be 'OFF'!

Servicing position

In the menu point 'Service position', the valves can be driven to a defined position for repair!

Note. The vehicle engine must not be running! The air conditioning system regulator(s) must not be 'OFF'!

Possible cause of fault

  1. Incorrect vehicle type selected in 9588 Porsche System Tester II
  2. 9588 Porsche System Tester II is not connected correctly or is faulty
  3. Power supply to the 'air-conditioning system regulator control module' is not OK
  4. Power supply to the 'gateway control module' is not OK
  5. 'K' lead' from diagnostic box to 'gateway control module' in instrument cluster does not function
  6. 'Gateway' in instrument cluster does not function
  7. 'CAN comfort (B)' does not function
  8. 'Air-conditioning system regulator control module' does not function

Affected pins

Diagnostic box

  1. Pin 1 'Power supply terminal 15/fuse carrier at left of dashboard, F 51)'
  2. Pin 3'K' lead'
  3. Pin 4 'Ground terminal 31'
  4. Pin 5 'Ground terminal 31'

Plug 'E' on front air-conditioning system regulator control module

  1. Pin 5 'Power supply terminal 30a/fuse carrier at right of dashboard, F 23)'
  2. Pin 9 'Ground input (terminal 31) MB 22'
  3. Pin 10 'Ground input (terminal 31) MB 22'

Plug 'C on front air-conditioning system regulator control module

  1. Pin 17' CAN comfort high'
  2. Pin 18 'CAN comfort low'

Scheme 528

Scheme 528: Diagnostic box in driver's footwell
Scheme 528: Diagnostic box in driver's footwell
PinDesignationPinDesignation
1Terminal 159Not used
2Not used10Not used
3K' lead (communication with Tester)11Not used
4Ground12Not used
5Ground13Not used
6CAN high diagnosis (instrument cluster)14CAN low diagnosis (instrument cluster)
7K lead15Not used
8Not used16Terminal 30

CONNECTOR PIN TERMINAL REFERENCE CHART

  1. Front air-conditioning system regulator control module faulty (manual, 2-zone and 4-zone air conditioning)
  2. Rear air-conditioning system regulator control module faulty (4-zone air conditioning)
  1. No or incorrect basic setting
  2. Short circuit to ground
  3. Open circuit/short circuit to B+
  4. Servo motor flap stiff
  5. Servo motor faulty
  6. Front air-conditioning system regulator faulty

Front air-conditioning system regulator control module: Plugs A and E

  1. Plug A: Pin 10 Temp, sensor signal (signal for evaporator temperature sensor)'
  2. Plug E: Pin 12 'Ground sensor'
  1. Short circuit to B+/ground/to each other or open circuit
  2. Vent flaps stiff
  3. Servo motor faulty
  4. Air-conditioning system regulator faulty

Air-conditioning system regulator control module, rear: Plugs B, C and D

  1. Plug B: Pin 8 'Right B-pillar flap (activate servo motor at rear right B-pillar)'
  2. Plug B: Pin 10 'Right B-pillar flap (activate servo motor at rear right B-pillar)'
  3. Plug C: Pin 6 'Right B-pillar flap (activate servo motor at rear right B-pillar)'
  4. Plug D: Pin 3 '5 V reference voltage'
  5. Plug D: Pin 7 'Ground signal'
  1. Short circuit to B+/ground/to each other or open circuit
  2. Servo motor flap stiff
  3. Servo motor faulty
  4. Air-conditioning system regulator faulty

Air-conditioning system regulator control module, rear: Plugs B, C and D

  1. Plug B: Pin 7 'Left B-pillar flap (activate servo motor at rear left B-pillar)'
  2. Plug C: Pin 3 'Left B-pillar flap (activate servo motor at rear left B-pillar)'
  3. Plug C: Pin 5 'Left B-pillar flap (feedback signal lead servo motor at rear left B-pillar)'
  4. Plug D: Pin 3 '5 V reference voltage'
  5. Plug D: Pin 7 'Ground signal'

Possible fault causes

Fault type 'lower limit value not reached'

  1. Refrigerant pressure < 1.4 bar (min. 2 sec.)

Fault type 'upper limit value exceeded'

  1. Refrigerant pressure > 32 bar (5 times within a single driving cycle)
  1. Upper limit value of power supply exceeded
  2. Lower limit value of power supply not reached
  3. Short circuit to ground
  4. Blower motor defective
  5. Air-conditioning system regulator faulty

Air-conditioning system regulator control module, rear: Plugs B, C and D

  1. Plug B: Pin 1 'Supply voltage (power supply of 12 V DC, rear blower regulator)'
  2. Plug C: Pin 12 'Blower regulator (control line, rear blower regulator)'
  3. Plug D: Pin 13 'Feedback voltage (feedback signal rear blower regulator)'
  1. Short circuit to B+/ground/to each other or open circuit
  2. Vent flaps stiff
  3. Servo motor faulty
  4. Air-conditioning system regulator faulty

Front air-conditioning system regulator control module: Plugs A and E

  1. Plug A: Pin 11 'Temp, valve (feedback signal lead for temperature valve)'
  2. Plug A: Pin 21 'Temp, valve (right temperature valve OPEN)'
  3. Plug A: Pin 22 'Temp, valve (right temperature valve CLOSED)'
  4. Plug E: Pin 1 '5 V reference voltage'
  5. Plug E: Pin 8 'Ground sensor'
  1. Vehicle voltage (battery voltage) exceeded
  2. Vehicle voltage (battery voltage) not reached
  3. Short circuit to ground
  4. Rear air-conditioning system regulator control module faulty

Air-conditioning system regulator control module, rear: Plug D

  1. Pin 1 'Term. 30A (power supply)'
  2. Pin 15 'Term. 31 (ground supply via ground pin MB22)'
  1. Vehicle voltage (battery voltage) exceeded
  2. Vehicle voltage (battery voltage) not reached
  3. Front air-conditioning system regulator control module faulty

Air-conditioning system regulator control module, front: Plug C

  1. Pin 12 'Feedback voltage (feedback voltage front blower regulator)'
  1. Short circuit to ground
  2. Open circuit/short circuit to B+
  3. Blower outlet sensor faulty
  4. Front air-conditioning system regulator faulty

Air-conditioning system regulator control module, front: plugs A and E

  1. Plug A: Pin 15 'Outlet temperature sensor (signal for left blower outlet sensor)'
  2. Plug E: Pin 12 'Ground sensor'
  1. Short circuit to ground
  2. Open circuit/short circuit to B+
  3. Blower outlet sensor faulty
  4. Front air-conditioning system regulator faulty

Air-conditioning system regulator control module, front: plugs A and E

  1. Plug A: Pin 5 'Outlet temperature sensor (signal for right blower outlet sensor)'
  2. Plug E: Pin 12 'Ground sensor'
  1. No or incorrect basic setting
  2. Short circuit to ground
  3. Open circuit/short circuit to B+
  4. Servo motor flap stiff
  5. Servo motor faulty
  6. Rear air-conditioning system regulator faulty

Air-conditioning system regulator control module, rear: Plugs B, C and D

  1. Plug B: Pin 2 'Air-flow flap (air-flow flap servo motor, rear left)'
  2. Plug B: Pin 4 'Air-flow flap (activation of air-flow flap servo motor, rear left)'
  3. Plug C: Pin 4 'Air-flow flap (feedback signal lead, air-flow flap servo motor, rear left)'
  4. Plug D: Pin 3 '5 V reference voltage'
  5. Plug D: Pin 7 'Ground signal'
  1. No or incorrect basic setting
  2. Short circuit to ground
  3. Open circuit/short circuit to B+
  4. Servo motor flap stiff
  5. Servo motor faulty
  6. Rear air-conditioning system regulator faulty

Air-conditioning system regulator control module, rear: Plugs B, C and D

  1. Plug B: Pin 3 'Air-flow flap (air-flow flap servo motor, rear right)'
  2. Plug B: Pin 5 'Air-flow flap (activation air-flow flap servo motor, rear right)'
  3. Plug C: Pin 7 'Air-flow flap (feedback signal lead, air-flow flap servo motor, rear right)'
  4. Plug D: Pin 3 '5 V reference voltage'
  5. Plug D: Pin 7 'Ground signal'
  1. No or inaccurate air-conditioning system regulator function (No display)
  2. No or inaccurate air-conditioning system regulator function (Cannot be checked now)
  1. No signal/communication
  2. Implausible signal
  1. Short circuit to ground
  2. Open circuit/short circuit to B+
  3. Short circuit between lines
  4. Blower outlet sensor faulty
  5. Rear air-conditioning system regulator faulty

Air-conditioning system regulator control module, rear: Plug D

  1. Pin 6 'Ground sensor'
  2. Pin 11 'Outlet temperature sensor (signal for rear left blower outlet sensor)'
  1. Short circuit to ground
  2. Open circuit/short circuit to B+
  3. Short circuit between lines
  4. Blower outlet sensor faulty
  5. Rear air-conditioning system regulator faulty

Air-conditioning system regulator control module, rear: Plug D

  1. Pin 6 'Ground sensor'
  2. Pin 10 'Outlet temperature sensor (signal for rear right blower outlet sensor)'
  1. Short circuit to B+
  2. Short circuit to ground
  3. Air-conditioning system regulator faulty
  1. 2-zone and 4-zone air conditioning systems

Front air-conditioning system regulator control module: Plug E, pin 1 '5 V reference voltage'

  1. Manual air conditioning

Front air-conditioning system regulator control module: Plug E, pin 1 '5 V reference voltage'

  1. Rear air-conditioning system regulator control module faulty
  2. CAN comfort faulty
  1. No or incorrect basic setting
  2. Short circuit to ground
  3. Open circuit/short circuit to B+
  4. Servo motor flap stiff
  5. Servo motor faulty
  6. Front air-conditioning system regulator faulty

Air-conditioning system regulator control module, front: Plugs A and E

  1. Plug A: Pin 1 'Passenger blower (servo motor for central vents)'
  2. Plug A: Pin 9 'Passenger blower (servo motor for central vents)'
  3. Plug A: Pin 14 'Passenger blower (feedback signal lead, servo motor for central vents)'
  4. Plug E: Pin 1 '5 V reference voltage'
  5. Plug E: Pin 8 'Ground signal'
  1. Vehicle voltage (battery voltage) exceeded
  2. Vehicle voltage (battery voltage) not reached
  3. Short circuit to ground
  4. Rear air-conditioning system regulator control module faulty

Air-conditioning system regulator control module, front: Plug E

  1. Pin 5 'Term. 30A (power supply)'
  2. Pin 9 'Term. 31 (ground supply line for ground pin 22)'
  3. Pin 10 'Term. 31 (ground supply line for ground pin 22)'
  1. Short circuit to ground
  2. Open circuit/short circuit to B+
  3. Sun sensor faulty
  4. Front air-conditioning system regulator control module faulty

Air-conditioning system regulator control module, front: Plugs C and E

  1. Plug C: Pin 7 'Left sun sensor signal'
  2. Plug C: Pin 15 'Right sun sensor signal'
  3. Plug E: Pin 1 '5 V reference voltage'
  4. Plug E: Pin 12 'Ground sensor'
  1. No or incorrect basic setting
  2. Short circuit to ground
  3. Open circuit/short circuit to B+
  4. Servo motor flap stiff
  5. Servo motor faulty
  6. Front air-conditioning system regulator faulty
  1. 2-zone and 4-zone air conditioning systems

Air-conditioning system regulator control module, front: Plugs A, C and E

  1. Plug A: Pin 2 'Defrost flap (feedback signal lead, defrost flap servo motor)'
  2. Plug C: Pin 6 'Defrost flap (defrost flap servo motor OPEN)'
  3. Plug C: Pin 24 'Defrost flap (defrost flap servo motor CLOSED)'
  4. Plug E: Pin 1 '5 V reference voltage'
  5. Plug E: Pin 8 'Ground signal'
  6. Manual air conditioning

Air-conditioning system regulator control module, front: Plugs A, C and E

  1. Plug A: Pin 1 'Defrost flap (defrost flap servo motor CLOSED)'
  2. Plug A: Pin 9 'Defrost flap (defrost flap servo motor OPEN)'
  3. Plug C: Pin 15 'Defrost flap (feedback signal lead, defrost flap servo motor)'
  4. Plug E: Pin 1 '5 V reference voltage'
  5. Plug E: Pin 8 'Ground signal'
  1. No or incorrect basic setting
  2. Short circuit to ground
  3. Open circuit/short circuit to B+
  4. Servo motor flap stiff
  5. Servo motor faulty
  6. Front air-conditioning system regulator faulty

Air-conditioning system regulator control module, front: Plugs A and E

  1. Plug A: Pin 11 'Footwell flap (feedback signal lead for left foot-well flap servo motor)'
  2. Plug A: Pin 21 'Footwell flap (servo motor for left footwell flap OPEN)'
  3. Plug A: Pin 22 'Footwell flap (servo motor for left footwell flap CLOSED)'
  4. Plug E: Pin 1 '5 V reference voltage'
  5. Plug E: Pin 8 'Ground signal'
  1. No or incorrect basic setting
  2. Short circuit to ground
  3. Open circuit/short circuit to B+
  4. Servo motor flap stiff
  5. Servo motor faulty
  6. Front air-conditioning system regulator faulty

Air-conditioning system regulator control module, front: Plugs B and E

  1. Plug B: Pin 14 'Footwell flap (feedback signal lead for right foot-well flap servo motor)'
  2. Plug B: Pin 19 'Footwell flap (servo motor for right footwell flap OPEN)'
  3. Plug B: Pin 20 'Footwell flap (servo motor for right footwell flap CLOSED)'
  4. Plug E: Pin 1 '5 V reference voltage'
  5. Plug E: Pin 8 'Ground signal'
  1. No or incorrect basic setting
  2. Short circuit to ground
  3. Open circuit/short circuit to B+
  4. Servo motor flap stiff
  5. Servo motor faulty
  6. Front air-conditioning system regulator faulty

Air-conditioning system regulator control module, front: Plugs A and E

  1. Plug A: Pin 1 'Passenger blower (servo motor for left central vents CLOSED)'
  2. Plug A: Pin 9 'Passenger blower (servo motor for left central vents OPEN)'
  3. Plug A: Pin 14 'Passenger blower (feedback signal lead, servo motor for left central vents)'
  4. Plug E: Pin 1 '5 V reference voltage'
  5. Plug E: Pin 8 'Ground signal'
  1. No or incorrect basic setting
  2. Short circuit to ground
  3. Open circuit/short circuit to B+
  4. Servo motor flap stiff
  5. Servo motor faulty
  6. Front air-conditioning system regulator faulty

Air-conditioning system regulator control module, front: Plugs B and E

  1. Plug B: Pin 10 'Passenger blower (feedback signal lead, servo motor for right central vents)'
  2. Plug B: Pin 17 'Passenger blower (servo motor for right central vents OPEN)'
  3. Plug B: Pin 18 'Passenger blower (servo motor for right central vents CLOSED)'
  4. Plug E: Pin 1 '5 V reference voltage'
  5. Plug E: Pin 8 'Ground signal'
  1. Open circuit/short circuit to B+
  2. Short circuit to ground
  3. Temperature sensor faulty
  4. Front air-conditioning system regulator control module faulty

Air-conditioning system regulator control module, front: Plugs A and E

  1. Plug A: Pin 4 'Air intake temperature sensor (air intake temperature sensor signal)'
  2. Plug E: Pin 12 'Ground sensor (ground sensors)'
  1. Short circuit to ground
  2. Open circuit/short circuit to B+
  3. Sun sensor faulty
  4. Front air-conditioning system regulator control module faulty

Air-conditioning system regulator control module, front: Plugs C and E

  1. Plug C: Pin 7 'Left sun sensor signal'
  2. Plug C: Pin 15 'Right sun sensor signal'
  3. Plug E: Pin 1 '5 V reference voltage'
  4. Plug E: Pin 12 'Ground sensor'
  1. Short circuit to ground
  2. Open circuit/short circuit to B+
  3. Temperature sensor faulty
  4. Front air-conditioning system regulator control module faulty
  1. Manual air conditioning

Air-conditioning system regulator control module, front: Plugs C and E

  1. Plug C: Pin 21 'Temp, sensor signal (signal for evaporator temperature sensor)'
  2. Plug E: Pin 12 'Ground sensor'
  1. Short circuit to B+
  2. Implausible signal
  3. Open circuit/short circuit to ground
  4. Pressure sensor faulty
  5. Front air-conditioning system regulator control module faulty

Air-conditioning system regulator control module, front: Plug C

  1. Pin 23 '(Pressure sensor)'
  1. Short circuit to B+
  2. Open circuit/short circuit to ground
  3. Electrical fault in electric circuit
  4. Air-conditioning compressor faulty
  5. Front air-conditioning system regulator control module faulty

Air-conditioning system regulator control module, front: Plug E

  1. Pin 4 'Externally-controlled compressor'
  2. Pin 11 'Externally-controlled compressor (freewheel-diode compressor)'
  1. Short circuit to ground
  2. Open circuit/short circuit to B+
  1. 2-zone and 4-zone air conditioning systems

Air-conditioning system regulator control module, front: Plug C

  1. Pin 14 'Auxiliary heater (water pump activation)'
  2. Manual air conditioning

Air-conditioning system regulator control module, front: Plug A

  1. Pin 18 'Auxiliary heater water pump'
  1. Air-conditioning system was not calibrated
  1. No display
  2. No or incorrect basic setting/adaptation
  3. Short circuit to ground
  4. Open circuit/short circuit to B+

Air-conditioning system regulator control module, front: Plugs A and E

  1. Plug A: Pin 14 'Air flap (feedback signal lead for temperature valve)'
  2. Plug A: Pin 23 'Air flap (right temperature valve OPEN)'
  3. Plug A: Pin 24 'Air flap (right temperature valve CLOSED)'
  4. Plug E: Pin 1 '5 V reference voltage'
  5. Plug E: Pin 8 'Ground sensor'
  1. CAN comfort, no signal/communication
  2. Additional heating control module switches to limp-home mode
  3. Air-conditioning system regulator control module faulty
  1. Short circuit to ground
  2. Open circuit/short circuit to B+
  3. Blower outlet sensor faulty
  4. Front air-conditioning system regulator faulty

Air-conditioning system regulator control module, front: Plugs A and E

  1. Plug A: Pin 7 'Outlet temperature sensor (signal for blower outlet sensor, front left footwell)'
  2. Plug E: Pin 12 'Ground sensor'
  1. Short circuit to ground
  2. Open circuit/short circuit to B+
  3. Blower outlet sensor faulty
  4. Front air-conditioning system regulator faulty

Air-conditioning system regulator control module, front: Plugs A and E

  1. Plug A: Pin 6 'Outlet temperature sensor (signal for blower outlet sensor, front right footwell)'
  2. Plug E: Pin 12 'Ground sensor'
  1. Short circuit to B+/ground/to each other or open circuit
  2. Servo motor flap stiff
  3. Servo motor faulty
  4. Air-conditioning system regulator faulty

Air-conditioning system regulator control module, front: Plugs A and E

  1. Plug A: Pin 13 Temp, valve (feedback signal lead for temperature valve)'
  2. Plug A: Pin 8 Temp, valve (right temperature valve OPEN)'
  3. Plug A: Pin 16 Temp, valve (right temperature valve CLOSED)'
  4. Plug E: Pin 1 '5 V reference voltage'
  5. Plug E: Pin 8 'Ground sensor'
  1. No signal/communication
  2. Implausible signal
  1. No signal/communication
  2. Please read out fault memory
  1. No signal/communication
  2. Air-conditioning system regulator control module faulty

Possible causes of faults

  1. Short circuit to ground
  2. Open circuit/short circuit to B+
  3. Seat heating faulty
  4. Seat heating control module faulty
  5. Rear air-conditioning system regulator faulty

Air-conditioning system regulator control module, rear: Plug C

  1. Pin 10 'Left seat heating (rear left seat heating)'
  1. Short circuit to ground
  2. Open circuit/short circuit to B+
  3. Seat heating faulty
  4. Seat heating control module faulty
  5. Rear air-conditioning system regulator faulty

Air-conditioning system regulator control module, rear: Plug C

  1. Pin 11 'Right seat heating (rear right seat heating)'
  1. Short circuit to ground
  2. Implausible signal
  3. Open circuit/short circuit to B+
  4. Air quality sensor faulty
  5. Front air-conditioning system regulator control module faulty

Air-conditioning system regulator control module, front: Plug C

  1. Pin 19 'Air quality sensor'
  1. Short circuit to B+/ground/to each other or open circuit
  2. Servo motor flap stiff
  3. Servo motor faulty
  4. Air-conditioning system regulator faulty
  1. 2-zone and 4-zone air conditioning systems

Air-conditioning system regulator control module, front: Plugs A and E

  1. Plug A: Pin 3 'Fresh-air/recirculation valve (feedback signal lead, servo motor for fresh-air/recirculation valve)'
  2. Plug A: Pin 17 'Fresh-air/recirculation valve (servo motor for fresh-air/recirculation valve OPEN)'
  3. Plug A: Pin 18 'Fresh-air/recirculation valve (servo motor for fresh-air/recirculation valve CLOSED)'
  4. Plug E: Pin 1 '5 V reference voltage'
  5. Plug E: Pin 8 'Ground signal'
  6. Manual air conditioning

Air-conditioning system regulator control module, front: Plug A

  1. Plug A: Pin 19 'Fresh-air/recirculation valve (servo motor for fresh-air/recirculation valve OPEN)'
  2. Plug A: Pin 20 'Fresh-air/recirculation valve (servo motor for fresh-air/recirculation valve CLOSED)'
  1. No or incorrect basic setting
  2. Short circuit to ground
  3. Open circuit/short circuit to B+
  4. Servo motor flap stiff
  5. Servo motor faulty
  6. Front air-conditioning system regulator faulty

Air-conditioning system regulator control module, front: Plugs A and E

  1. Plug A: Pin 8 'Left temp, valve (left temperature valve OPEN)'
  2. Plug A: Pin 13 'Left temp, valve (feedback signal lead for left temperature valve)'
  3. Plug A: Pin 16 'Left temp, valve (left temperature valve CLOSED)'
  4. Plug E: Pin 1 '5 V reference voltage'
  5. Plug E: Pin 8 'Ground signal'
  1. No or incorrect basic setting
  2. Short circuit to ground
  3. Open circuit/short circuit to B+
  4. Servo motor flap stiff
  5. Servo motor faulty
  6. Front air-conditioning system regulator faulty

Air-conditioning system regulator control module, front: Plugs A and E

  1. Plug A: Pin 12 'Right temp, valve (feedback signal lead for right temperature valve)'
  2. Plug A: Pin 19 'Right temp, valve (right temperature valve OPEN)'
  3. Plug A: Pin 20 'Right temp, valve (right temperature valve CLOSED)'
  4. Plug E: Pin 1 '5 V reference voltage' Plug E: Pin 8 'Ground signal'
  1. Short circuit to B+
  2. Short circuit or open circuit
  3. Short circuit to ground
  4. Servo motor flap stiff
  5. Servo motor faulty
  6. Rear air-conditioning system regulator faulty

Air-conditioning system regulator control module, rear: Plugs B, C and D

  1. Plug B: Pin 9 'Passenger blower (passenger blower, rear left tunnel OPEN)1
  2. Plug C: Pin 2 'Passenger blower (passenger blower, rear left tunnel CLOSED)1
  3. Plug C: Pin 16 'Passenger blower (feedback signal lead, passenger blower, rear left tunnel)'
  4. Plug D: Pin 3 '5 V reference voltage'
  5. Plug D: Pin 7 'Ground signal'
  1. Short circuit to B+
  2. Short circuit or open circuit
  3. Short circuit to ground
  4. Servo motor flap stiff
  5. Servo motor faulty
  6. Rear air-conditioning system regulator faulty

Air-conditioning system regulator control module, rear: Plugs B, C and D

  1. Plug B: Pin 16 'Passenger blower (passenger blower, rear right tunnel OPEN)1
  2. Plug B: Pin 17 'Passenger blower (passenger blower, rear right tunnel CLOSED)'
  3. Plug C: Pin 13 'Passenger blower (feedback signal lead, passenger blower, rear right tunnel)'
  4. Plug D: Pin 3 '5 V reference voltage'
  5. Plug D: Pin 7 'Ground signal'
  1. Short circuit to B+
  2. Short circuit or open circuit
  3. Short circuit to ground
  4. Servo motor flap stiff
  5. Servo motor faulty
  6. Rear air-conditioning system regulator faulty

Air-conditioning system regulator control module, rear: Plugs B, C and D

  1. Plug B: Pin 14 'Left temp, valve (servo motor for rear left temperature valve OPEN)'
  2. Plug B: Pin 15 'Left temp, valve (servo motor for rear left temperature valve CLOSED)'
  3. Plug C: Pin 14 'Left temp, valve (feedback signal lead, servo motor for rear left temperature valve)'
  4. Plug D: Pin 3 '5 V reference voltage'
  5. Plug D: Pin 7 'Ground signal'
  1. Short circuit to B+
  2. Short circuit or open circuit
  3. Short circuit to ground
  4. Servo motor flap stiff
  5. Servo motor faulty
  6. Rear air-conditioning system regulator faulty

Air-conditioning system regulator control module, rear: Plugs B, C and D

  1. Plug B: Pin 12 'Right temp, valve (servo motor for rear right temperature valve OPEN)'
  2. Plug B: Pin 13 'Right temp, valve (servo motor for rear right temperature valve CLOSED)'
  3. Plug C: Pin 15 'Right temp, valve (feedback signal lead, servo motor for rear right temperature valve)'
  4. Plug D: Pin 3 '5 V reference voltage'
  5. Plug D: Pin 7 'Ground signal'
  1. No or incorrect basic setting
  2. Short circuit to ground
  3. Open circuit/short circuit to B+
  4. Servo motor flap stiff
  5. Servo motor faulty
  6. Front air-conditioning system regulator faulty

Air-conditioning system regulator control module, front: Plugs A and E

  1. Plug A: Pin 11 'Footwell flap (feedback signal lead for footwell flap servo motor)'
  2. Plug A: Pin 21 'Footwell flap (servo motor for footwell flap OPEN)'
  3. Plug A: Pin 22 'Footwell flap (servo motor for footwell flap CLOSED)'
  4. Plug E: Pin 1 '5 V reference voltage'
  5. Plug E: Pin 8 'Ground signal'

For manual air conditioning system

  1. Fault in servo motor for front air distribution, Refer to " «SERVO MOTOR FOR FRONT AIR DISTRIBUTION»(ref-286047-S22156451842008052900000) "

For 2-zone air conditioning system

  1. No or incorrect basic setting
  2. Short circuit to ground
  3. Open circuit/short circuit to B+
  4. Servo motor flap stiff
  5. Servo motor faulty
  6. Front air-conditioning system regulator faulty

Air-conditioning system regulator control unit, front: Plugs A, C and E

  1. Plug A: Pin 23 'Passenger blower (servo motor for left side vents OPEN)'
  2. Plug A: Pin 24 'Passenger blower (servo motor for left side vents CLOSED)'
  3. Plug C: Pin 5 'Passenger blower (feedback signal lead, servo motor for left side vents)'
  4. Connector E: Pin 1 '5 V reference voltage'
  5. Connector E: Pin 8 'Ground signal'
  1. Short circuit to ground
  2. Open circuit/short circuit to B+
  3. Blower regulator faulty
  4. Blower motor faulty
  5. Front air-conditioning system regulator faulty
  1. 2-zone and 4-zone air conditioning systems

Air-conditioning system regulator control module, front: Plug C

  1. Pin 8 'Supply voltage (power supply to front blower regulator)'
  2. Manual air conditioning

Air-conditioning system regulator control module, front: Plug A

  1. Pin 'Supply voltage (power supply to front blower regulator)'
  1. Short circuit to ground
  2. Open circuit/short circuit to B+
  3. Blower regulator faulty
  4. Blower motor faulty
  5. Rear air-conditioning system regulator faulty

Air-conditioning system regulator control module, rear: Plug B

  1. Pin 1 'Supply voltage (power supply to rear blower regulator)'
  1. CAN comfort, no signal/communication
  2. Additional heating control module switches to limp-home mode
  3. Air-conditioning system regulator control module faulty
  1. Short circuit to B+
  2. Short circuit or open circuit
  3. Short circuit to ground
  4. Servo motor flap stiff
  5. Servo motor faulty
  6. Air-conditioning system regulator faulty

Air-conditioning system regulator control module, front: Plugs A, C and E

  1. Plug A: Pin 23 'Servo motor for left side vents open'
  2. Plug A: Pin 24 'Servo motor for left side vents closed'
  3. Plug C: Pin 5 'Feedback signal for left side vents'
  4. Plug E: Pin 1 '5 V reference voltage'.
  5. Plug E: Pin 8 'Ground signal'
  1. Short circuit to B+
  2. Short circuit or open circuit
  3. Short circuit to ground
  4. Servo motor flap stiff
  5. Servo motor faulty
  6. Air-conditioning system regulator faulty

Air-conditioning system regulator control module, front: Plugs B and E

  1. Plug B: Pin 1 'Passenger blower (servo motor for right side vents OPEN)'
  2. Plug B: Pin 5 'Passenger blower (feedback signal lead, servo motor for right side vents)'
  3. Plug B: Pin 9 'Passenger blower (servo motor for right side vents CLOSED)'
  4. Plug E: Pin 1 '5 V reference voltage'
  5. Plug E: Pin 8 'Ground signal'
  1. Short circuit to ground
  2. Open circuit/short circuit to B+
  1. 2-zone and 4-zone air conditioning systems

Air-conditioning system regulator control module, front: Plug C

  1. Pin 14 'Auxiliary heater (water pump activation)'
  2. Manual air conditioning

Air-conditioning system regulator control module, front: Plug A

  1. Pin 18 'Auxiliary heater water pump'
  1. No or inaccurate air-conditioning system regulator function (Short circuit to ground)
  2. No or inaccurate air-conditioning system regulator function (Open circuit/short circuit to B+)

Air-conditioning system regulator control module, plug C

  1. Pin 23 'DS (air-conditioning pressure sensor)'
  1. Short circuit to B+
  2. Short circuit or open circuit
  3. Short circuit to ground
  4. Servo motor flap stiff
  5. Servo motor faulty
  6. Rear air-conditioning system regulator faulty

Air-conditioning system regulator control module, rear: Plugs B, C and D

  1. Plug B: Pin 9 'Passenger blower (passenger blower, rear left tunnel OPEN)'
  2. Plug C: Pin 2 'Passenger blower (passenger blower, rear left tunnel CLOSED)'
  3. Plug C: Pin 16 'Passenger blower (feedback signal lead, passenger blower, rear left tunnel)'
  4. Plug D: Pin 3 '5 V reference voltage'
  5. Plug D: Pin 7 'Ground signal'
  1. Short circuit to B+
  2. Short circuit or open circuit
  3. Short circuit to ground
  4. Servo motor flap stiff
  5. Servo motor faulty
  6. Rear air-conditioning system regulator faulty

Air-conditioning system regulator control module, rear: Plugs B, C and D

  1. Plug B: Pin 16 'Passenger blower (passenger blower, rear right tunnel OPEN)'
  2. Plug B: Pin 17 'Passenger blower (passenger blower, rear right tunnel CLOSED)'
  3. Plug C: Pin 13 'Passenger blower (feedback signal lead, passenger blower, rear right tunnel)'
  4. Plug D: Pin 3 '5 V reference voltage'
  5. Plug D: Pin 7 'Ground signal'
  1. Short circuit to B+
  2. Short circuit or open circuit
  3. Short circuit to ground
  4. Servo motor flap stiff
  5. Servo motor faulty
  6. Rear air-conditioning system regulator faulty

Air-conditioning system regulator control module, rear: Plugs B, C and D

  1. Plug B: Pin 14 'Left temp, valve (servo motor for rear left temperature valve OPEN)'
  2. Plug B: Pin 15 'Left temp, valve (servo motor for rear left temperature valve CLOSED)'
  3. Plug C: Pin 14 'Left temp, valve (feedback signal lead, servo motor for rear left temperature valve)'
  4. Plug D: Pin 3 '5 V reference voltage'
  5. Plug D: Pin 7 'Ground signal'
  1. Short circuit to B+
  2. Short circuit or open circuit
  3. Short circuit to ground
  4. Servo motor flap stiff
  5. Servo motor faulty
  6. Rear air-conditioning system regulator faulty

Air-conditioning system regulator control module, rear: Plugs B, C and D

  1. Plug B: Pin 12 'Right temp, valve (servo motor for rear right temperature valve OPEN)'
  2. Plug B: Pin 13 'Right temp, valve (servo motor for rear right temperature valve CLOSED)'
  3. Plug C: Pin 15 'Right temp, valve (feedback signal lead, servo motor for rear right temperature valve)'
  4. Plug D: Pin 3 '5 V reference voltage'
  5. Plug D: Pin 7 'Ground signal'

More articles — Air Conditioning - Diagnostics