| Test | Tester | Check | Notes | Nominal | ||
|---|---|---|---|---|---|---|
| Step | Multimeter MKM-587-A | of | between | Value | ||
| 03 | Voltmeter range 20 V, DC | Voltage supply, compressor magnetic clutch Y1 | Wiring harness plug Y1 (BRBL/ brown-blue) | Ground | · Disconnect relay K60 Bridge Ter. 30 (4) with Ter. 87 (8) of compressor relay K60 using adapter lead |
· Disconnect wiring harness plug from Y1
· Ignition ON
· Switch S101 ON
Important: radiator fan and auxiliary fan start running.
| » 11.5 V | ||
|---|---|---|
| Ohmmeter range 200 W | Wiring harness plug Y1 (BRGE/ brown- yellow) | |
| Ground | · Disconnect wiring harness plug from Y1 |
· Ignition OFF
| » 0.5 W |
|---|
| Note: |
Compressor relay K60 switches on the compressor magnetic clutch Y1 when the following conditions are fulfilled:
- Compressor clutch can only engage when the engine is running.
- Engine running at nominal idle speed, operating temperature.
- Ambient temperature > 4°C/40 °F.
- Air conditioning switched on.
- Low pressure in refrigerant circuit > 180 kPa (1.8 bar).
- High pressure in refrigerant circuit < 3000 kPa (30 bar).
- Vehicles with C 14 NZ engine and power steering: power steering pressure switch S61 closed.
- Pressure at switch S61 < 4000 kPa (40 bar).
Possible cause of fault, trouble-shooting
1. MAXI fuse F15/30A defective.
2. Fuse F17/10A defective.
3. Fuse F20/30A defective.
4. Lead interruption between wiring harness plug for compressor magnetic clutch Y1 (BRBL/brown-blue) and compressor relay K60 (8).
5. Lead interruption between wiring harness plug for compressor magnetic clutch Y1 (BRGE/brown-yellow) and coolant temperature switch S128 (1).
6. Lead interruption between grounding point 2 and coolant temperature switch S128 (3).
7. AC relay K6 defective - see test step 07.
8. AC switch S101 defective - see test step 08.
9. Pressure switch ASSY. S20 defective - see test step 06.
10. Compressor relay K60 defective - see test step 11.
11. Power steering pressure switch S61 defective - see test step 19 (only for C 14 NZ with power steering).
12. Coolant temperature switch S128 defective - see test step 15.
( ) Terminal in wiring harness plug