Vauxhall Workshop Service and Repair Manuals

Cooling Fan Inoperative - 2H0, LDE, LDD, LLU, or LUJ

Diagnostic Instructions

Diagnostic Fault Information

Circuit/System Description

The engine cooling fan system is composed of one fan, 3 relays, the engine control module (ECM), and the associated wiring. The fan assembly includes two resistors, which enable the fan to operate at 3 speeds.

Low Speed

In low speed operation, the ECM provides ground from ECM terminal 44 X1. The Cooling Fan Low Speed Relay activates and provides power to the cooling fan motor through cooling fan motor terminal 2 and the internal fan resistor.

Medium Speed

In medium speed operation, the ECM provides ground from ECM terminal 15 X1. The Cooling Fan Medium Speed 1 Relay activates and provides power to the cooling fan motor through cooling fan motor terminal 3 and the internal fan resistor.

High Speed

In high speed operation, the ECM provides ground to ECM terminals 15 X1 and 44 X1. As previously described, power is now provided to both cooling fan terminals 2 and 3. In addition, power and ground are now provided to the coil of the Cooling Fan High Speed Relay. The Cooling Fan High Speed Relay activates and provides power to the cooling fan motor through cooling fan terminal 4.

Reference Information

Schematic Reference

Engine Cooling Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Cooling System Description and Operation

Electrical Information Reference

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Verify that DTCs P0480, or P0481 are not set.

⇒	If a DTC is set, refer to DTC P0480 or P0481

2. Command the Cooling Fan Relay 1 ON and OFF with a scan tool. The cooling fan motor should turn ON at low speed and OFF when changing between the commanded states.

⇒	If the cooling fan motor does not operate correctly, refer to Low Speed Operation Malfunction.

3. Command the Cooling Fan Relays 2 and 3 ON and OFF with a scan tool. The cooling fan motor should turn ON at medium speed and OFF when changing between the commanded states.

⇒	If the cooling fan motor does not operate correctly, refer to Medium Speed Operation Malfunction.

4. If all previous tests normal, refer to High Speed Operation Malfunction.

Circuit/System Testing

Note:  You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.

Low Speed Operation Malfunction

1. Ignition OFF, disconnect the KR20C Cooling Fan Low Speed Relay.
2. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal 86 and ground.

⇒	If the test lamp does not illuminate, replace the X50A Fuse Block - Underbonnet.

3. Verify that a test lamp illuminates between the B+ circuit terminal 30 and ground.

⇒	If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the X50A Fuse Block - Underhood.

4. Connect a test lamp between the ignition circuit terminal 86 and the control circuit terminal 85.
5. Command the Cooling Fan Relay 1 ON with a scan tool. The test lamp should illuminate.

⇒	If the test lamp does not illuminate, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module.

6. Ignition OFF, disconnect the harness connector at the G10 Cooling Fan Motor.
7. Verify that a test lamp illuminates between the ground circuit terminal 1 and B+.

⇒	If the test lamp does not illuminate, test the ground circuit for an open/high resistance.

8. Connect the harness connector at the G10 Cooling Fan Motor.
9. Install a 40 A fused jumper wire between the B+ circuit terminal 30 and the control circuit terminal 87 and verify the G10 Cooling Fan Motor is activated.

⇒	If the G10 Cooling Fan Motor is not activated, test the control circuit for a short circuit to ground or an open circuit/high resistance. If the circuit tests normal, replace the G10 Cooling Fan Motor.

10. If all circuit tests normal, test or replace the KR20C Cooling Fan Low Speed Relay.

Medium Speed Operation Malfunction

1. Ignition OFF, disconnect the KR20P Cooling Fan Medium Speed Relay.
2. Ignition ON, verify that a test lamp illuminates between the circuit terminals listed below and ground.

•	KR20P Cooling Fan Medium Speed Relay B+ circuit terminal 30

•	KR20P Cooling Fan Medium Speed Relay ignition circuit terminal 86

⇒	If the test lamp does not illuminate, replace the X50A Fuse Block - Underbonnet.

3. Connect a test lamp between the ignition circuit terminal 86 and the control circuit terminal 85.
4. Command the Cooling Fan Relays 2 and 3 ON with a scan tool. The test lamp should illuminate.

⇒	If the test lamp does not illuminate, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module.

5. Install a 60 A fused jumper wire between the B+ circuit terminal 30 and the control circuit terminal 87 and verify the G10 Cooling Fan Motor is activated.

⇒	If the G10 Cooling Fan Motor is not activated, test the control circuit for a short circuit to ground or an open circuit/high resistance. If the circuit tests normal, replace the G10 Cooling Fan Motor.

6. If all circuits test normal, test or replace the KR20P Cooling Fan Medium Speed Relay.

High Speed Operation Malfunction

1. Ignition OFF, disconnect the KR20D Cooling Fan High Speed Relay.
2. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal 86 and ground.

⇒	If the test lamp does not illuminate, replace the X50A Fuse Block - Underbonnet.

3. Connect a test lamp between the ignition circuit terminal 30 and ground.
4. Command the Cooling Fan Relay 1 ON with a scan tool. The test lamp should illuminate.

⇒	If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the X50A Fuse Block - Underhood.

5. Connect a test lamp between the ignition circuit terminal 86 and control circuit terminal 85.
6. Command the Cooling Fan Relays 2 and 3 ON with a scan tool. The test lamp should illuminate.

⇒	If the test lamp does not illuminate, replace the X50A Fuse Block - Underbonnet.

7. Install a 60 A fused jumper wire between B+ and the control circuit terminal 87 and verify the G10 Cooling Fan Motor is activated.

⇒	If the G10 Cooling Fan Motor is not activated, test the control circuit for a short circuit to ground or an open circuit/high resistance. If the circuit tests normal, replace the G10 Cooling Fan Motor.

8. If all circuit tests normal, test or replace the KR20D Cooling Fan High Speed Relay.

Component Testing

Relay Test

1. Ignition OFF, disconnect the cooling fan relay.
2. Test for 70-110 Ω between terminals 85 and 86.
3. Test for infinite resistance between the following terminals:

•

30 and 86

•

30 and 87

•

30 and 85

•

85 and 87

⇒	If not the specified range, replace the relay.

4. Test for less than 2 Ω between terminals 30 and 87A.

⇒	If greater than the specified range, replace the relay.

5. Install a 20 A fused jumper wire between relay terminal 85 and 12 V. Install a jumper wire between relay terminal 86 and ground. Test for less than 2 Ω between terminals 30 and 87.

⇒	If greater than the specified range, replace the relay.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.