Circuit/System Testing
- Ignition OFF and vehicle systems OFF, disconnect the X2 harness connector at the K73 telematics communication interface control module, ignition ON.
- Test for less than 4 V between the signal circuits listed below and ground
- Signal + Circuit Terminal 1
- Signal - Circuit Terminal 2
- If greater than 4 V
- Ignition OFF, disconnect the X1 harness connector at the A11 Radio, ignition ON.
- Test for less than 1 V between the signal circuits and ground.
- If greater than 1 V, repair the short to voltage in the circuit.
- If less then 1 V, replace the A11 Radio.
- If less than 4 V
- Ignition OFF.
- Test for infinite resistance between the K73 telematics communication interface control module signal circuits listed below and ground
- Signal + Circuit Terminal 1
- Signal - Circuit Terminal 2
- If less than infinite resistance
Repair the short to ground on the circuit.
- If infinite resistance
- Disconnect the X1 harness connector at the A11 Radio.
- Test for less than 2 Ω in the signal circuits listed below end to end.
- Signal + Circuit Terminal 1
- Signal - Circuit Terminal 2
- If 2 Ω or greater
Repair the open/high resistance in the circuit.
- If less than 2 Ω
- Replace the K73 telematics communication interface control module.
- Verify that the Connecting to OnStar® message is heard clearly through the audio system when the OnStar® blue button is pressed.
- If audio is not heard clearly
Replace the A11 radio.
- If audio is heard clearly
- If audio is not heard clearly
- All OK.