Circuit/System Testing

Ignition OFF and all vehicle systems OFF, disconnect the harness connector for the appropriate A9 Outside Rearview Mirror. It may take up to 2 min for all vehicle systems to power down.
- X510 - Driver Door Harness to Outside Rearview Mirror
- X610 - Passenger Door Harness to Outside Rearview Mirror
Test for less than 10 Ω between the ground circuit terminal 5 and ground.
- If 10 Ω or greater
1. Ignition OFF.
2. 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.
- If less than 10 Ω
Ignition ON, connect a test lamp between the control circuit terminal 18 and the ground circuit terminal 5.
Verify the test lamp turns ON and OFF when commanding the Object Detection Alert Indicators On and Off with a scan tool.
- If the test lamp is always OFF
1. Ignition OFF, disconnect the harness connector at the appropriate B218 Side Object Sensor Module.
2. Test for infinite resistance between the control circuit and ground.
  - If less than infinite resistance, repair the short to ground on the circuit.
  - If infinite resistance
3. 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 B218 Side Object Sensor Module.
- If the test lamp is always ON
1. Ignition OFF, disconnect the harness connector at the B218 Side Object Sensor Module, ignition ON.
2. Test for less than 1 V between the control circuit and ground.
  - If 1 V or greater, repair the short to voltage on the circuit.
  - If less than 1 V, replace the B218 Side Object Sensor Module.
- If the test lamp turns ON and OFF
Test or replace the A9 Outside Rearview Mirror Glass.