Without UE1
- Ignition OFF, disconnect the harness connector at the inside rearview mirror.
- Ignition ON, test for 8.5-9.5 volts between the cellular microphone signal circuit terminal 10 and ground.
- If less than specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the radio.
- If greater than specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the radio.
- Ignition ON, test for less then 1 volt between the terminal 2 and ground.
- If greater then specified range, test for a short to voltage. If the circuit tests normal, replace the radio.
- If all circuits test normal, replace the inside rearview mirror assembly.