Circuit/System Testing
Rear Fog Lamp Switch Malfunction
- Ignition OFF, scan tool disconnected, all doors closed, all accessories OFF, open and close drivers door, disconnect the harness connector at the S30 Headlamp Switch. It may take up to 2 min for all vehicle systems to power down.
- Test for less than 10 Ω between the ground circuit terminal 8 and ground.
- If 10 Ω or greater
- Ignition OFF.
- Test for less than 2 Ω in the ground circuit end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω, repair the open/high resistance in the ground connection.
- Go to next step: If less than 10 Ω
- Ignition ON.
- Verify the scan tool Rear Fog Lamp Switch parameter is Inactive.
- If not Inactive
- Ignition OFF, disconnect the X1 harness connector at the K9 Body Control Module.
- Test for infinite resistance between the signal circuit terminal 6 and ground.
- If less than infinite resistance, repair the short to ground on the circuit.
- If infinite resistance, replace the K9 Body Control Module.
- Go to next step: If Inactive
- Install a 3 A fused jumper wire between the signal circuit terminal 6 and ground.
- Verify the scan tool Rear Fog Lamp Switch parameter is Active.
- If not Active
- Ignition OFF, disconnect the X1 harness connector at the K9 Body Control Module, ignition ON.
- Test for less than 1 V between the signal circuit terminal 6 and ground.
- If 1 V or greater, repair the short to voltage on the circuit.
- Go to next step: If less than 1 V
- Test for less than 2 Ω in the signal circuit end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω, replace the K9 Body Control Module.
- Go to next step: If Active
- Test or replace the S30 Headlamp Switch.
Rear Fog Lamp Malfunction
- Ignition OFF, exterior lamps OFF, disconnect the harness connector at the E29R Fog Lamp - Rear. It may take up to 2 min for all vehicle systems to power down.
- Test for less than 5 Ω between the ground circuit terminal 1 and ground.
- If 5 Ω or greater
- Ignition OFF.
- Test for less than 2 Ω in the ground circuit end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω, repair the open/high resistance in the ground connection.
- Go to next step: If less than 5 Ω
- Connect a test lamp between the control circuit terminal 2 and ground, ignition ON.
- Verify the test lamp turns ON and OFF when commanding the Rear Fog Lamp ON and OFF with a scan tool.
- If the test lamp is always OFF
- Ignition OFF, disconnect the X5 harness connector at the K9 Body Control Module.
- Test for infinite resistance between the control circuit and ground.
- If less than infinite resistance, repair the short to ground on the circuit.
- Go to next step: If infinite resistance
- Test for less than 2 Ω in the control circuit end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω, replace the K9 Body Control Module.
- If the test lamp is always ON
- Ignition OFF, disconnect the X5 harness connector at the K9 Body Control Module, ignition ON.
- Test for less than 1 V between the control circuit terminal and ground.
- If 1 V or greater, repair the short to voltage on the circuit.
- If less than 1 V, replace the K9 Body Control Module.
- Go to next step: If the test lamp turns ON and OFF
- Test or replace the E29R Fog Lamp - Rear.