Component Description: OnStar®: Notes
OnStar® equipped, RPO UE1, vehicles use the radio amplifier and speaker system for voice communication from the OnStar® operator to the vehicle. Voice communication from the vehicle to the OnStar® operator is through the OnStar® microphone and module, which is not a part of the radio system.
When OnStar® begins operation, the radio volume is set to a preset level, autotone preset for OnStar® becomes active and the fade control is adjusted to the full front speakers. The radio volume control can then be used to adjust the volume to a desired level.
The radio system and OnStar® system are connected through the 12-way connector at the back of the radio. Left and right channel OnStar® audio, mute control of radio functions by OnStar®, and the audio signal ground are the circuits provided in the 12-way connector.
Disconnecting the 12-way connector from the radio will isolate the radio system from the OnStar® system. Voice communication from the vehicle to the OnStar® operator could be possible under this condition. However, the vehicle occupant will not be able to hear the OnStar® operator.
For more information regarding radio operation problems, refer to Symptoms - Entertainment and Diagnostic System Check - Vehicle in Vehicle DTC Information. For further information regarding OnStar® operation, refer to the OnStar® section of this service manual.