Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the appropriate A9 outside rearview mirror.
- Wait 1 minute, test for less than 10 Ω between the ground circuit terminal E and ground.
- If greater than the specified range, test the ground circuit for an open/high resistance.
- Connect a test lamp between the heater element control circuit terminal F and ground.
- Engine running, operate the rear window defogger ON and OFF with the rear defogger switch. The test lamp should turn ON and OFF when changing between the commanded states.
- If the test lamp is always ON, test the control circuit for a short to voltage.
- If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance.
- If all circuits test normal, test or replace the outside rearview mirror glass.