72646 - L10 CLIMATE CONTROL NOT COOLING

The fan works normally and sends air to the passenger compartment according to the pre-set flows bu the air remains at the outside temperature and is not cooled.
The enablement of the engagement of the refrigerant circuit is controlled by both the climate control system control unit and the engine management control unit. Therefore if the climate control system is not cooling in certain conditions, this is correct.
STEPOPERATIONS TO BE CARRIED OUTTEST RESULTS
0PRELIMINARY CHECKSALL OKPROBLEMS ENCOUNTEREDACTION
Check the condition of the compressor drive beltMove on to Step Belt deterioratedReplace the belt    See in Op. 1092G10 Engine components single drive BELT - R.R.
1CHECK USING DIAGNOSTIC EQUIPMENTALL OKPROBLEMS ENCOUNTEREDACTION
With the tester (Examiner or other instrument) connected, check the CAN network information for:

  • no control unit not activated;
  • that there are no faulty control units;
  • no control unit with faulty CAN line;
Move on to Step 1. Presence of faults1. Continue following the instructions for the diagnostic equipment
2. Error detected in the climate control system control unitMove on to Step
3. Error detected in the engine management control unitMove on to Step
2CHECK USING DIAGNOSTIC EQUIPMENTALL OKPROBLEMS ENCOUNTEREDACTION
Keeping the diagnostic equipment (Examiner or other instruments) connected to the diagnostic socket, check:

  • that there are no faults in the climate control system node
  • parameter plausibility
Move on to Step 1. Presence of faults1. Continue following the instructions for the diagnostic equipment
2. Parameters not plausible2. Continue following the instructions for the diagnostic equipment
3. No communication between climate control system control unit3. Restore connection between the climate control unit and diagnostic connector (Wiring Diagram ) E6020 AIR CONDITIONING
3CHECK USING DIAGNOSTIC EQUIPMENTALL OKPROBLEMS ENCOUNTEREDACTION
2.4 20 V,2.0 TB,3.0 V6Keeping the diagnostic equipment (Examiner or other instruments) connected to the diagnostic socket, check:

  • that there are no faults in the engine management node
  • parameter plausibility
Move on to Step 1. Presence of faults1.Continue following the instructions for the diagnostic equipment
2. Parameters not plausible2. Continue following the instructions for the diagnostic equipment
3. Climate control circuit pressure not correctMove on to Step
4. No dialogue with the engine management control unit4. Restore connection between the climate control unit and diagnostic connector (Wiring Diagram ) E5030 PETROL ENGINE ELECTRONIC MANAGEMENT
3CHECK USING DIAGNOSTIC EQUIPMENTALL OKPROBLEMS ENCOUNTEREDACTION
2.4 JTD 10VKeeping the diagnostic equipment (Examiner or other instruments) connected to the diagnostic socket, check:

  • that there are no faults in the engine management node
  • parameter plausibility
Move on to Step 1. Presence of faults1. Continue following the instructions for the diagnostic equipment
2. Parameters not plausible2. Continue following the instructions for the diagnostic equipment
3. Climate control circuit pressure not correctMove on to Step
4. No dialogue with the engine management control unit4. Restore connection between the climate control unit and diagnostic connector (Wiring Diagram ) E5050 DIESEL ENGINE ELECTRONIC MANAGEMENT
4SYSTEM PRESSURE CHECKALL OKPROBLEMS ENCOUNTEREDACTION
Check the system pressure    Continue following the instructions in the test 5040B Air conditioning system operational check (pressure)Move on to Step Pressure not correctEliminate leaks and top up climate control system to correct level    See in Op. 5040A10 Air conditioning coolant circuit - Drying and Repressurizing
5CHECK USING DIAGNOSTIC EQUIPMENTALL OKPROBLEMS ENCOUNTEREDACTION
Keeping the diagnostic equipment (Examiner or other instruments) connected to the diagnostic socket, check the following at the climate control node:

  • the operation of the compressor engagement relay through active diagnosis, making sure that the compressor electro-magnet coupling is not activated at the same time;
Move on to Step 1. relay does not come on and coupling not activatedMove on to Step
2. relay comes on and coupling not activatedMove on to Step
6RELAY ELECTRICAL CIRCUIT CHECKALL OKPROBLEMS ENCOUNTEREDACTION
Check the continuity of the relay operating circuitMove on to Step 1. Connections not correct1. Restore the connections (Wiring Diagram ) E6021 COMPRESSOR ENGAGEMENT
2. Relay faulty2. Replace the relay
7COMPRESSOR ELECTRICAL CIRCUIT CHECKALL OKPROBLEMS ENCOUNTEREDACTION
Check the continuity of the compressor power circuitMove on to Step 1. Connections not correct1. Restore the connections (Wiring Diagram ) E6021 COMPRESSOR ENGAGEMENT
2. Electro-magnet coupling faulty2. Replace the compressor complete with coupling    See in Op. 5040A20 Air conditioning COMPRESSOR - R.R. - Includes fluid level check and top up if necessary
8CHECK ON CORRECT OPERATIONALL OKPROBLEMS ENCOUNTEREDACTION
Check that the fault is no longer presentFault persistsReplace the climate control system control unit    See in Op. 5040D18 Air conditioning CONTROL UNIT - R.R.