Components In Engine Compartment, Servicing

Heating And A/C Components In Engine Compartment, Servicing







CAUTION:
Before beginning repairs:
- Switch off all electrical consumers.
- Switch off ignition.
- Remove ignition key from ignition switch.

NOTE:
- System components marked with an asterisk * can only be serviced or replaced after discharging refrigerant system. Use Kent Moore ACR4 or equivalent.
- Before carrying out any work on the A/C refrigerant system, refer to A/C refrigerant system safety measures.

1. Damper with low pressure service valve*
- In refrigerant hose from expansion valve to compressor.
- Only use Kent Moore ACR4 or equivalent
2. Refrigerant hose*
- From expansion valve to compressor
- With damper
3. Refrigerant pipe*
- From receiver dryer to expansion valve
4. High pressure service valve*
- Only use Kent Moore ACR4 or equivalent
5. A/C pressure switch -F129- or high pressure sensor -G65-
- Switch/sensor can be removed without discharging refrigerant system.
- Tightening torque 8 Nm (71 in.lb)
- Always replace O ring.
- -F129- checking
- -G65- checking
- -F129- and -G65- can also be checked using VAS 5051 in mode "Guided Fault Finding".
- -G65- is monitored by OBD of ECM.

Function:
- -F129- switches coolant fan -V7- to the next higher speed when pressure increases in refrigerant circuit.
- -F129- switches off A/C clutch whenever excessive refrigerant system pressure is present (e.g.: insufficient air flow over condensor or if system is overcharged).
- -F129- switches off A/C clutch whenever insufficient refrigerant system pressure is present (e.g.: refrigerant has leaked out).
- -G65- supplies refrigerant system pressure signal to coolant fan control module -J293- and engine control module.

6. Expansion valve*
7. Dust and pollen filter
- With activated charcoal filter
8. Ambient temperature switch -F38-
- Switches off A/C clutch -N25- at low outside temperatures.
- Off at -1 degree C (30 degrees F).
- On at +7 degrees C (45 degrees F).
9. A/C cut-out thermal switch -F163- through 04.99
- Switches off A/C clutch -N25- at excessively high coolant temperatures.
- Off at 119 degrees C (246 degrees F)
- On at 112 degrees C (234 degrees F).

NOTE: -F163- deleted from 05.99. Thermal cut-out function assumed by Engine Coolant Temperature (ECT) Sensor -G62- via Engine Control Module (ECM).

10. Evaporator water drain valve
- Checking see Fig. 1
11. Coolant Fan Control (FC) Control Module -J293-
12. Refrigerant hose*
- From expansion valve to compressor
- With damper
13. Refrigerant hose*
- From compressor to condenser
14. Condenser*
15. Pressure relief valve*
16. Compressor*
- Manufacturer: Sanden, designation: SD7V16
- Manufacturer: Zexel, designation: DCW-17D
17. A/C clutch -N25-
- Sanden, servicing.
- Zexel, servicing.
18. Receiver drier*

Fig. 1 Evaporator water drain valve, checking







- Fold cover -1- in bulkhead insulation mat -3- upwards.
- Remove drain valve -2- from opening in bulkhead -4-.

Check water drain valve as follows:
- The water drain valve must not be stuck.
- Insulation mat must not be deformed or damaged in area of valve.
- The opening in the sealing cap of the water drain valve must point down.

NOTE: When the cover cap -1-is closed, it must be flush with the insulation matting. If the cover cap -1- is pushed in too far, the water drain valve sealing cap -2- can jam.