Cruze

DTC P0685, P0689, or P0690

The powertrain relay is an electrical switch that opens and closes under the control of the engine control module. The powertrain relay switch is held in the open position by spring tension. Battery positive voltage is supplied directly to the relay coil and the relay switch contact at all times. The engine control module (ECM) supplies the ground path to the relay coil control circuit through an output driver module. The output driver module for the ignition main relay also incorporates a fault detection circuit, which is continuously monitored by the ECM. When the ECM commands the powertrain relay ON, switched battery voltage is supplied to fuses in the under bonnet fuse block. The switched battery voltage that is supplied to the ECM, provides power to the internal ECM circuits associated with the throttle actuator control (TAC) operation. The ECM also monitors the voltage level on the switched battery circuit to confirm that the powertrain relay contacts have closed.

P0685 00

The ECM detects that the commanded state of the driver and the actual state of the control circuit do not match for greater than 2 s.

P0689 00

The ECM detects the engine controls powertrain relay feedback circuit is less than 5 V when the relay is commanded ON for 5 s.

P0690 00

DTCs P0685 00, P0689 00, and P0690 00 are Type B DTCs.

DTCs P0685 00, P0689 00, and P0690 00 are Type B DTCs.

Schematic Reference

Engine Controls Schematics

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

Note: If You were sent here from Engine Cranks But Does Not Run proceed to Circuit/System Testing.

1. Ignition OFF, allow the ECM to completely power down. Probe both test points of F9, F10, and F11 fuses supplied with voltage by the KR75 Powertrain Relay. The test lamp should not illuminate on any test point of any fuse.
2. Ignition ON, probe both test points of F9, F10, and F11 fuses supplied with voltage by the KR75 Powertrain Relay. The test lamp should illuminate on at lease one test point of each fuse.
3. Operate the vehicle within the conditions for running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the freeze frame/failure records data.

1. Ignition OFF, disconnect the KR75 Powertrain Relay.
2. Ignition ON, verify that a test lamp illuminates between the KR75 Powertrain Relay coil B+ socket circuit terminal 85 and ground.

⇒	If the test lamp does not illuminate, repair the KR75 Powertrain Relay coil B+ circuit for a short to ground or an open/high resistance.

3. Ignition OFF, connect a test lamp between the KR75 Powertrain Relay coil control socket circuit terminal 86 and the relay coil B+ socket circuit terminal 85.

⇒	If the test lamp is always ON, test the KR75 Powertrain Relay coil control circuit for a short to ground. If the circuit tests normal, replace the K20 Engine Control Module.

4. Ignition ON. The test lamp should turn ON.

⇒	If the test lamp is always OFF, test the KR75 Powertrain Relay coil control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module.

Note: The ignition voltage circuit is between the KR75 Powertrain Relay circuit 87 and the ECM through fuse F10. The ignition voltage is a feedback circuit.

5. Install a 15 A fused jumper wire between the KR75 Powertrain Relay switch B+ socket circuit terminal 30 and the KR75 Powertrain Relay switch ignition voltage socket circuit terminal 87.
6. Attempt to start the engine. The engine should start.
7. If the engine does not start, test the KR75 Powertrain Relay switch ignition voltage circuit between the KR75 Powertrain Relay circuit terminal 87 and the ECM connector X2 terminals 3 and 5 for a short to ground or for an open/high resistance. If the circuit tests normal, replace the K20 Engine Control Module.
8. If all circuits test normal, test or replace the KR75 Powertrain Relay.

Relay Test

1. Ignition OFF, disconnect the KR75 Powertrain Relay.
2. Measure for 70-110 Ω between terminals 85 and 86 of the KR75 Powertrain Relay.

⇒	If the resistance is not within the specified range, replace the KR75 Powertrain Relay.

3. Measure for infinite resistance between following terminals of the KR75 Powertrain Relay:

•	Terminals 30 and 86

•	Terminals 30 and 87

•	Terminals 30 and 85

•	Terminals 85 and 87

⇒	If continuity is detected, replace the KR75 Powertrain Relay.

4. Connect a 20 A fused jumper wire from the positive terminal of the battery to KR75 Powertrain Relay terminal 85. Connect a jumper wire from the negative terminal of the battery to KR75 Powertrain Relay terminal 86. Measure for less than 5 Ω between KR75 Powertrain Relay terminal 30 and KR75 Powertrain Relay socket terminal 87.

⇒	If the resistance measures more than 5 Ω, replace the KR75 Powertrain Relay.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.