Circuit/System Testing
DTC B3885
- Ignition OFF.
- Connect a test lamp between the control circuit terminal 7 (circuit 5185 GY) at the X88 Trailer Connector and ground, ignition ON.
- Verify the test lamp turns ON and OFF when commanding the Left Trailer Tail Lamp ON and OFF with a scan tool.
- If the test lamp is always OFF
- Ignition OFF, disconnect the X1 harness connector at the K101 Trailer Interface Control Module.
- Test for infinite resistance between the control circuit terminal and ground.
- If less than infinite resistance, repair the short to ground on the circuits.
- If infinite resistance
- Test for less than 2 Ω in the control circuits end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω, replace the K101 Trailer Interface Control Module.
- If the test lamp is always ON
- Ignition OFF, disconnect the X1 harness connector at the K101 Trailer Interface 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 K101 Trailer Interface Control Module.
- Go to next step: If the test lamp turns ON and OFF
- Test or replace the X88 Trailer Connector.
DTC B3886
- Ignition OFF.
- Connect a test lamp between the control circuit terminal 5 (circuit 5184 BN/GY) at the X88 Trailer Connector and ground, ignition ON.
- Verify the test lamp turns ON and OFF when commanding the Right Trailer Tail Lamp ON and OFF with a scan tool.
- If the test lamp is always OFF
- Ignition OFF, disconnect the X1 harness connector at the K101 Trailer Interface Control Module.
- Test for infinite resistance between the control circuit terminal and ground.
- If less than infinite resistance, repair the short to ground on the circuits.
- If infinite resistance
- Test for less than 2 Ω in the control circuits end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω, replace the K101 Trailer Interface Control Module.
- If the test lamp is always ON
- Ignition OFF, disconnect the X1 harness connector at the K101 Trailer Interface 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 K101 Trailer Interface Control Module.
- Go to next step: If the test lamp turns ON and OFF
- Test or replace the X88 Trailer Connector.