When a Holden Assist® keypress is made, a serial data message is sent to the audio system to mute all radio functions and output Holden Assist® originated audio. After the audio system is muted, the telematics module transmits signals to the audio system on the audio signal circuit, and returned to the module on the audio common circuit.

Schematic Reference

Connector End View Reference

Component Connector End Views

Description and Operation

Electrical Information Reference

Scan Tool Reference

Control Module References for scan tool information

1. Tune radio to a known good station and verify the audio is heard clearly through all speaker channels.

⇒	If audio is not heard clearly, refer to Speaker Malfunction.

2. Ignition ON, radio ON, set volume to comfortable level and press Holden Assist® Call Center button. Verify Connecting to Holden Assist® message is heard clearly through the audio system.

⇒	If Holden Assist® message is noisy or distorted, refer to Circuit/System Testing.

1. Ignition OFF, disconnect the X2 harness connector at the telematics module.
2. Test for less than 5 Ω between terminal 2 and ground.

⇒	If greater than the specified range, test the circuit for an open or high resistance. If the circuit tests normal, replace the radio.

3. Disconnect the X4 harness connector at the radio.
4. Ignition OFF, test for less than 5 Ω of resistance between the Telephone Audio Signal (+) terminal 7 at the radio and the Telephone Audio Signal (+) terminal 15 at the telematics module.

⇒	If greater than the specified range, test the circuit for a short to voltage, short to ground, or an open/high resistance.

5. If all circuits test normal, replace the telematics module.
6. Ignition ON, radio ON, verify Holden Assist® audio has improved.

⇒	If the audio is still poor, replace the radio.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for radio or telematics module replacement, setup, and programming.