Circuit/System Testing
WARNING: This page is about a different car, the 2008 Cadillac STS. However, it is still accessible from the selected car via links, so may be relevant.
- Ignition OFF, disconnect the harness connector at the inside rearview mirror.
- Ignition OFF, doors closed, interior lamps OFF, test for less than 5 ohms between the inside rearview mirror ground circuit terminal 8 and ground.
- If greater than specified range, test the ground circuit for an open/high resistance.
- Ignition ON, test for 9.5-10.5 volts between the keypad supply voltage circuit terminal 12 and ground.
- If less than specified range, test the voltage supply circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the VCIM.
- If greater than specified range, test the voltage supply circuit for a short to voltage. If the circuit tests normal, replace the VCIM.
- Test for less than 1 volt between the keypad signal circuit terminal 11 ground.
- If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the VCIM.
- Test for 9.5-10.5 volts between the keypad supply voltage circuit terminal 12 and the keypad signal circuit terminal 11.
- If not within the specified range, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the VCIM.
- Ignition OFF, disconnect the X1 harness connector at the VCIM.
- Ignition OFF, test for infinite resistance between the keypad signal circuit terminal 11 and ground.
- If less than the specified value, test the signal circuit for a short to ground.
- If all circuits test normal, replace the inside rearview mirror.