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 warnings through the left front speaker. The radio receives audible warning requests via the class 2 serial data line. If the radio receives multiple audible warning requests, the warning with the highest priority sounds first. The Multifunction Alarm generates the audible warnings on vehicles with RPO UL5 -- Radio Delete Option. The following lists the audible warning priority and the pulse rate:

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

Door Ajar Warning

The radio activates the door ajar audible warning as requested by the body control module (BCM). The BCM sends a class 2 message to the radio indicating the chime frequency of a medium rate and at a continuous duration. The door ajar warning sounds and the door ajar indicator illuminates when the following occurs:

  1. The body control module (BCM) determines that the driver's door is open and the signal circuit low. The IPC receives a message via class 2 from the BCM requesting illumination of the door ajar indicator.
  2. The vehicle is not in park. The BCM receives a class 2 message from the PCM indicating the gear position.

Fasten Safety Belt Warning

The radio activates the fasten safety belt audible warning as requested by the IPC. The IPC sends a class 2 message to the radio indicating the chime frequency of a slow rate and at a duration of 8 seconds. The fasten safety belt warning sounds and the fasten safety belt indicator illuminates when the following occurs:

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

If the seat belt is buckled when the ignition is turned on, the chime does not sound. If the seat belt is buckled while the chime is sounding, the chime stops. If the seat belt is unbuckled after the initial transition to ON, the chime does not sound.

Key-In-Ignition Warning

The radio activates the key-in-ignition audible warning as requested by the IPC. The IPC sends a class 2 message to the radio indicating the chime frequency of a medium rate and at a continuous duration. The key-in-ignition warning sounds when the following occurs:

    • The ignition switch is OFF.
    • The body control module (BCM) determines that the driver's door is open and the signal circuit is low. The IPC receives a class 2 message from the BCM indicating the door ajar status.
    • The BCM determines that the key-in-ignition switch is open and the signal circuit is high. The IPC receives a class 2 message from the BCM indicating the key-in-ignition status.

Lights On Warning

The radio activates the lights on warning as requested by the body control module (BCM). The BCM sends a class 2 message to the radio indicating the chime frequency of a fast rate and at a continuous duration.

    • The ignition is OFF.
    • The BCM determines that the driver door is open and the signal circuit is low.
    • The BCM determines that the headlamp switch is in the park or head position.

Park Brake Warning

The radio activates the park brake audible warning as requested by the IPC. The IPC sends a class 2 message to the radio indicating the chime frequency of a medium rate and at a continuous duration. The park brake warning sounds and the BRAKE indicator illuminates when the following occurs:

    • The ignition is on.
    • The vehicle is not in park. The IPC receives a class 2 message from the PCM indicating the gear position.
    • The IPC determines that the park brake is engaged and the signal circuit is low.

Turn Signal On

The radio activates the turn signal on audible warning as requested by the body control module (BCM). The BCM sends a class 2 message to the radio indicating the chime frequency of a fast rate and at a duration 2 seconds.

Additional Warnings

The following warnings have an associated IPC or message center indicator.

    • ABS
        The radio activates the audible warning as requested by the IPC. The IPC sends a class 2 message to the radio indicating the chime frequency of a fast rate and a duration of 4 times.
    • BRAKE
        The radio activates the audible warning as requested by the IPC. The IPC sends a class 2 message to the radio indicating the chime frequency of a fast rate and a duration of 4 times.
    • Charging System
        The radio activates the audible warning as requested by the IPC. The IPC sends a class 2 message to the radio indicating the chime frequency of a fast rate and a duration of 4 times.
    • Hot Coolant Temperature
        The radio activates the audible warning as requested by the IPC. The IPC sends a class 2 message to the radio indicating the chime frequency of a fast rate and at a duration of every three seconds.
    • Low Coolant Level
        The radio activates the audible warning as requested by the IPC. The IPC sends a class 2 message to the radio indicating the chime frequency of a fast rate and a duration of 4 times.
    • LOW OIL PRESSURE
        The radio activates the audible warning as requested by the IPC. The IPC sends a class 2 message to the radio indicating the chime frequency of a fast rate and at a duration of every three seconds.
    • Low Fuel
        The radio activates the audible warning as requested by the IPC. The IPC sends a class 2 message to the radio indicating the chime frequency of a fast rate and a duration of 4 times.
    • Low Oil Level
        The radio activates the audible warning as requested by the IPC. The IPC sends a class 2 message to the radio indicating the chime frequency of a fast rate and a duration of 4 times.
    • SERVICE TRACTION SYSTEM
        The radio activates the audible warning as requested by the IPC. The IPC sends a class 2 message to the radio indicating the chime frequency of a fast rate and a duration of 4 times.
    • SERVICE VEHICLE SOON
        The radio activates the audible warning as requested by the IPC. The IPC sends a class 2 message to the radio indicating the chime frequency of a fast rate and a duration of 4 times.

Refer to Indicator/Warning Message Description and Operation .