Cruze

DTC P0691-P0694 - LDE, LXV or 2H0

The engine control module (ECM) commands the fan ON in either high speed, medium speed, or low speed, depending on cooling requirements. In low speed, the fan is turned ON at a reduced speed. In medium speed, the fan is turned ON at a higher reduced speed. In high speed, the fan is turned ON at full speed. In low speed operation, the ECM provides ground to ECM terminal 51 X1. The cooling fan relay activates and provides ground to the coils of the cooling fan medium speed 2 relay and the cooling fan speed control relay. The cooling fan speed control relay activates and provides power to the coil of the cooling fan high speed relay. The cooling fan high speed relay remains inactive because ECM terminal 71 X2 is not grounded. The cooling fan medium speed 2 relay provides power to the engine cooling fan motor through cooling fan terminal 3 and the internal fan resistor. In medium speed operation, the ECM provides ground to ECM terminal 71 X2. The cooling fan high speed relay remains inactive because power is not provided to the coil from the cooling fan speed control relay. The cooling fan medium speed 1 relay activates and provides power to the engine cooling fan motor through cooling fan terminal 2 and the internal fan resistor. In high speed operation, the ECM provides ground to ECM terminals 51 X1 and 71 X2. 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 engine cooling fan motor through cooling fan terminal 4, bypassing the resistors.

P0691 00

The ECM detects a short to ground or open circuit on the cooling fan relay control circuit for more than 1 s.

P0692 00

The ECM detects a short to voltage on the cooling fan relay control circuit for more than 1 s.

P0693 00

The ECM detects a short to ground or open circuit on the cooling fan high speed relay control circuit for more than 1 s.

P0694 00

The ECM detects a short to voltage on the cooling fan high speed relay control circuit for more than 1 s.

DTCs P0691 00, P0692 00, P0693 00 and P0694 00 are Type B DTCs.

DTCs P0691 00, P0692 00, P0693 00 and P0694 00 are Type B DTCs.

Schematic Reference

Connector End View Reference

Component Connector End Views

Electrical Information Reference

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

1. Command the Cooling Fan speed 1 with a scan tool. The fan should turn ON at low speed.

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

2. Command the Cooling Fan speed 2 with a scan tool. The fan should turn ON at medium speed.

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

3. Command the Cooling Fan speed 3 with a scan tool. The fan should turn ON at high speed.

⇒	If the fan does not operate correctly, refer to High Speed Malfunction.

Note: Circuit/System Verification must be performed before Circuit/System Testing.

Low Speed Malfunction

1. Ignition OFF, remove the relays listed below:

•	KR20B Cooling Fan Medium Speed 2 Relay

•	KR20E Cooling Fan Speed Control Relay

•	KR20F Cooling Fan Relay

2. Ignition ON, verify that a test lamp does not illuminate between relay controlled output circuit terminal of the relay connectors listed below and ground:

•	KR20B Cooling Fan Medium Speed 2 Relay terminal 87

•	KR20E Cooling Fan Speed Control Relay terminal 87

⇒	If the test lamp illuminates, test the output circuit for a short to voltage.

3. Ignition OFF, test for less than 5 Ω between the relay controlled output circuit terminal 87 of the KR20F Cooling Fan Relay and ground.

⇒	If greater than the specified range, test the output circuit for an open/high resistance.

4. Ignition ON, verify that a test lamp illuminates between the relay coil ignition circuit terminal of each relay connector listed below and ground:

•	KR20B Cooling Fan Medium Speed 2 Relay terminal 86

•	KR20F Cooling Fan Relay terminal 86

⇒

If the test lamp does not illuminate, test the relay coil ignition circuit for a short to ground or an open/high resistance. If the circuit tests normal and the ignition circuit fuse is open, test the relay switch controlled output circuit terminal 87 at the KR20E Cooling Fan Speed Control Relay connector for a short to ground. If the circuit tests normal, test or replace the KR20E Cooling Fan Speed Control Relay.

5. Verify that a test lamp illuminates between the relay switch B+ circuit terminal 30 of the KR20B Cooling Fan Medium Speed 2 Relay connector 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 and the B+ circuit fuse is open, test the relay controlled output circuit terminal at the relay connectors listed below for a short to ground:

•	KR20B Cooling Fan Medium Speed 2 Relay terminal 87

•	KR20A Cooling Fan Medium Speed 1 Relay terminal 30

6. Install a 10 A fused jumper wire between the relay coil ignition circuit terminal 86 and the relay coil control circuit terminal 85 of the KR20B Cooling Fan Medium Speed 2 Relay connector.
7. Verify that a test lamp illuminates between the relay switch ignition circuit terminal 30 and the relay controlled output circuit terminal 87 at the KR20F Cooling Fan Relay connector.

⇒	If the test lamp does not illuminate, test the relay switch ignition circuit terminal 30 at the KR20F Cooling Fan Relay connector for an open/high resistance.

8. Ignition OFF, disconnect the harness connector at the G10 Cooling Fan Motor.
9. Test for less than 5 Ω between the G10 Cooling Fan Motor ground circuit terminal 1 and ground.

⇒	If greater than the specified range, test the ground circuit for an open/high resistance.

10. Connect the harness connector at the G10 Cooling Fan Motor.
11. Connect a 30 A fused jumper wire between the relay switch B+ circuit terminal 30 and the relay controlled output circuit terminal 87 of the KR20B Cooling Fan Medium Speed 2 Relay connector. Verify the cooling fan is activated at low speed.

⇒	If the cooling fan does not activate at low speed, test the output circuit for an open/high resistance. If the circuit tests normal, test or replace the cooling fan.

12. Ignition ON, verify that a test lamp does not illuminate between the relay coil control circuit terminal of the KR20F Cooling Fan Relay connector and ground.

⇒	If the test lamp illuminates, test the control circuit for a short to voltage. If the circuit tests normal, replace the K20 Engine Control Module.

13. Connect a test lamp between the relay coil ignition circuit terminal 86 and relay coil control circuit terminal 85 at the KR20F Cooling Fan Relay connector.
14. Command the Cooling Fan to Speed 1 with a scan tool. Verify that the test lamp illuminates.

⇒	If the test lamp does not turn OFF, test the relay coil control circuit for a short to ground. If the circuit tests normal, replace the K20 Engine Control Module.

⇒	If the test lamp does not turn ON, test the control circuit for an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module.

15. If all circuits test normal, test or replace the relays listed below:

•	KR20B Cooling Fan Medium Speed 2 Relay

•	KR20F Cooling Fan Relay

Medium Speed Malfunction

1. Ignition OFF, disconnect the KR20A Cooling Fan Medium Speed 1 Relay.
2. Ignition ON, verify that a test lamp does not illuminate between the relay controlled output circuit terminal 30 and ground.

⇒	If the test lamp illuminates, test the output circuit for a short to voltage.

3. Verify that a test lamp illuminates between the relay coil ignition circuit terminal 86 and ground.

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

4. Verify that a test lamp illuminates between the relay switch B+ circuit terminal 87 and ground.

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

5. Verify that a test lamp does not illuminate between the relay coil control circuit terminal 85 and ground.

⇒	If the test lamp illuminates, test the control circuit for a short to voltage. If the circuit tests normal, test the KR20E Cooling Fan Speed Control Relay for correct operation. If the relay tests normal, replace the K20 Engine Control Module.

6. Connect a 30 A fused jumper wire between the relay switch B+ circuit terminal 87 and the relay controlled output circuit terminal 30. Verify the cooling fan is activated at medium speed.

⇒	If the cooling fan does not activate, test the output circuit for an open/high resistance. If the circuit tests normal, test or replace the G10 Cooling Fan Motor.

7. Connect a test lamp between the relay coil ignition circuit terminal 86 and relay coil control circuit terminal 85 at the KR20A Cooling Fan Medium Speed 1 Relay connector.
8. Command the Cooling Fan to Speed 2 with a scan tool. Verify that the test lamp illuminates.

⇒	If the test lamp does not turn OFF, test the relay coil control circuit for a short to ground. If the circuit tests normal, replace the K20 Engine Control Module.

⇒	If the test lamp does not turn ON, test the control circuit for an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module.

9. If all circuits test normal, test or replace the KR20A Cooling Fan Medium Speed 1 Relay.

High Speed Malfunction

1. Ignition OFF, disconnect the relays listed below:

•	KR20D Cooling Fan High Speed Relay

•	KR20E Cooling Fan Speed Control Relay

2. Ignition ON, verify that a test lamp does not illuminate between the relay controlled output circuit terminal 30 at the KR20D Cooling Fan High Speed Relay connector and ground.

⇒	If the test lamp illuminates, test the output circuit for a short to voltage.

3. Verify that a test lamp illuminates between the relay coil ignition circuit terminal 86 of the KR20E Cooling Fan Speed Control Relay connector and ground.

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

4. Verify that a test lamp illuminates between the relay switch ignition circuit terminal 30 of the KR20E Cooling Fan Speed Control Relay connector and ground.

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

5. Install a 10 A fused jumper wire between the relay switch ignition circuit terminal 30 and the relay controlled output circuit terminal 87 of the KR20E Cooling Fan Speed Control Relay connector.
6. Verify that a test lamp illuminates between the relay coil ignition circuit terminal 86 of the KR20D Cooling Fan High Speed Relay connector and ground.

⇒	If the test lamp does not illuminate, test the ignition circuit terminal 86 of the KR20D Cooling Fan High Speed Relay connector for an open/high resistance.

7. Verify that a test lamp illuminates between the relay switch B+ circuit terminal 87 of the KR20D Cooling Fan High Speed Relay connector 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 and the B+ circuit fuse is open, test the relay controlled output circuit for a short to ground. If the circuit tests normal, test or replace the G10 Cooling Fan Motor.

8. Connect a 30 A fused jumper wire between the relay switch B+ circuit terminal 87 and the relay controlled output circuit terminal 30 of the KR20D Cooling Fan High Speed Relay connector. Verify the cooling fan is activated at high speed.

⇒	If the cooling fan does not activate at high speed, test the output circuit for an open/high resistance. If the circuit tests normal, test or replace the G10 Cooling Fan Motor.

9. Connect a test lamp between the relay coil ignition circuit terminal 86 and relay coil control circuit terminal 85 at the KR20D Cooling Fan High Speed Relay connector.
10. Command the Cooling Fan to Speed 3 with a scan tool. Verify that the test lamp illuminates.

⇒	If the test lamp does not turn ON, test the control circuit for an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module.

11. If all circuits test normal, test or replace the relays listed below:

•	KR20D Cooling Fan High Speed Relay

•	KR20E Cooling Fan Speed Control Relay

Relay Test

1. Ignition OFF, remove the applicable relay.
2. Test for 70-110 Ω between terminals 85 and 86 of the relay.

⇒	If not within the specified range, replace the relay.

3. Test for infinite resistance between the following terminals:

•

30 and 85

•

30 and 86

•

30 and 87

•

85 and 87

⇒	If less than the specified value, replace the relay.

4. Install a 10 A fused jumper wire between relay terminal 85 and B+. Install a jumper wire between relay terminal 86 and ground. Test for less than 5 Ω between terminals 30 and 87.

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

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Engine Control Module Replacement for ECM replacement, setup, and programming