Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the appropriate outside rearview mirror.
- Test for less than 10 ohms between the ground circuit terminal 5 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 6 and ground.
- Ignition ON, 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, replace outside rear view mirror glass.