GM Service Manual Online
For 1990-2009 cars only

The audible warnings alert the driver of a system concern or a critical vehicle condition. The radio generates the audible warning through the left front speaker. The radio receives audible warning requests via the class 2 serial data circuit. If the radio receives multiple audible warning requests, the warning with the highest priority is activated first. The following lists the audible warning priority and the pulse rate:

  1. Fast rate chime - 200 pulses per minute
  2. Medium rate chime - 150 pulses per minute
  3. Slow rate chime - 50 pulses per minute
  4. Single chime

Door Ajar Warning

The radio receives a class 2 message from the instrument panel cluster (IPC) in order to activate a continuous, medium rate chime. The appropriate door ajar message illuminates in the driver information center (DIC) and the audible warning is activated when the following occurs:

    • The IPC receives a class 2 message from the driver door module (DDM) indicating that a door is open. The signal circuit is low.
    • The vehicle speed is greater than 4.8 km/h (3 mph). The IPC uses the vehicle speed signal circuit from the powertrain control module in order to calculate the vehicle speed.

Fasten Safety Belt Warning

The radio receives a class 2 message from the IPC in order to activate an 8 second, slow rate chime. The fasten safety belt indicator illuminates and the audible warning is activated when the following occurs:

    • The ignition switch transitions to ON.
    • The IPC receives a class 2 message from the inflatable restraint sensing and diagnostic module (SDM) indicating that the driver seat belt is not buckled.

The chime is not activated if the seat belt is buckled when the ignition is turned on or if the seat belt is unbuckled after the initial transition to ON. The chime stops If the seat belt is buckled while the chime is activated.

Key-In-Ignition Warning

The radio receives a class 2 message from the Instrument panel module (IPM) in order to activate a continuous, medium rate chime. The key-in-ignition audible warning is activated when the following occurs:

    • The key is in the ignition, grounding the key in ignition switch signal circuit.
        The IPM monitors the key in ignition switch signal circuit.
    • The IPM receives a class 2 message from the DDM indicating that the driver door is open. The signal circuit is low.

Lights On Warning

The radio receives a class 2 message from the dash integration module (DIM) in order to activate a continuous, fast rate chime. The LIGHTS ON message illuminates in the DIC and the audible warning is activated when the following occurs:

    • The key is removed from the ignition.
    • The DIM receives a class 2 message from the DDM indicating that the driver door is open.
    • The DIM determines that the headlamp switch is in the PARK or the HEAD position.

Additional Warnings

The following warnings have an associated IPC indicator or DIC message:

    • ABS
        The radio receives a class 2 message from the IPC in order to activate a single chime.
    • Engine Coolant
        The radio receives a class 2 message from the IPC in order to activate 5 chimes at a medium rate.
    • Engine Oil Pressure
        The radio receives a class 2 message from the IPC in order to activate 5 chimes at a medium rate.
    • ENGINE OVERHEATED STOP ENGINE -- 42
        The radio receives a class 2 message from the IPC in order to activate a continuous, medium rate chime.
    • FUEL LEVEL LOW -- 11
        The radio receives a class 2 message from the IPC in order to activate a single chime.
    • OIL PRESSURE LOW STOP ENGINE -- 35
        The radio receives a class 2 message from the IPC in order to activate 5 chimes at a medium rate.
    • SERVICE STABILITY SYS -- 54
        The radio receives a class 2 message from the IPC in order to activate a single chime.
    • TRANS HOT IDLE ENGINE -- 112
        The radio receives a class 2 message from the IPC in order to activate a continuous, medium rate chime.
    • TURN SIGNAL ON -- 20
        The radio receives a class 2 message from the IPC in order to activate a single chime per turn signal pulse.

For further information on the indicators and warning messages, refer to Indicator/Warning Message Description and Operation .