GM Service Manual Online
For 1990-2009 cars only

Circuit Operation

Ignition Positions

    • OFF
        The radio receives battery voltage at all times on the BLU/YEL wire through the DOME Fuse in order to keep the clock and the preset station memory alive.
    • ACCY or RUN
         Voltage is applied to the GRY wire through the CIG Fuse in order to enable the radio operation. The radio is grounded through the G 202.
       - The radio illumination is controlled by the instrument panel lamp dimmer.
       - The PARK or HEAD headlamp positions:
       - Voltage is applied through the dimmer control and to the radio panel lamp and the internal circuitry.

Compact Disc and Cassette Player

The compact disc (CD) or cassette player is part of the radio unit, if equipped. When operating, the same power required by the radio is necessary for the tape or CD player operation.