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 serial data circuit. If the radio receives multiple audible warning requests, the warning with the highest priority sounds first. On vehicles without a radio, a chime module generates the audible warnings and receives audible warning requests via the serial data circuit. Either the radio or the chime module is the chime procedure. 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

Fasten Safety Belt Warning

The chime producer activates the fasten safety belt audible warning as requested by the body control module (BCM). The BCM sends a serial data message to the audio amplifier indicating the chime frequency at a slow rate and 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 drivers seat belt is not buckled and the signal is low. The SDM sends a serial data message to the BCM indicating the seat belt status. The instrument panel cluster (IPC) receives a serial data message from the BCM 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.

Lights On Warning

The chime producer activates the lights on warning as requested by the body control module (BCM). The BCM sends a serial data message to the chime producer indicating the chime frequency of a fast rate and at a continuous duration. The lights on warning sounds when the following occurs:

    • 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.

Brake Warning

The chime producer activates the brake audible warning as requested by the instrument panel cluster (IPC). The IPC sends a serial data message to the chime producer indicating the chime frequency of a fast rate and at a continuous duration. The brake warning sounds and the BRAKE indicator illuminates when the following occurs:

    • The ignition is ON.
    • The vehicle speed is greater than 8 km/h (4.9 mph). The IPC receives a serial data message from the engine control module (ECM) indicating the vehicle speed.
    • The IPC determines that the park brake is engaged and the signal circuit is low.
    • The brake fluid is low.
    • The Traction Control System (TCS) and the Vehicle Stability Enhancement System (VSES) have failed.

Key-In-Ignition Warning

The chime producer activates the key-in-ignition audible warning as requested by the body control module (BCM). The BCM sends a serial data message to the chime producer indicating the chime frequency of a medium rate and continuous duration. The key-in-ignition warning sounds when the following occurs:

    • The ignition switch is OFF.
    • The BCM determines that the driver door is open and the signal circuit is low. The IPC also receives a serial data 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 serial data message from the BCM indicating the key-in-ignition status.

Door Ajar Warning

The chime producer activates the door ajar audible warning as requested by the body control module (BCM). The BCM sends a serial data message to the chime producer indicating the chime frequency of a medium rate and continuous duration. The door ajar warning sounds and the appropriate door ajar indicator illuminates in the drivers information center (DIC) when the following occurs:

    • The BCM determines that a door (driver door, passenger door, left rear door, right rear door) is open and the signal circuit is low. The IPC also receives a serial data message from the BCM indicating the door ajar status.
    • The vehicle is not in PARK. The BCM receives a serial data message from the engine control module (ECM)/BCM indicating the gear position.

Additional Warnings

The following warnings have an associated instrument panel cluster (IPC) indicator or driver information center (DIC) message:

    • Battery Voltage Low Message--The chime producer activates the audible warning as requested by the body control module (BCM). The BCM sends a serial data message to the chime producer indicating the chime frequency of a fast rate and at a continuous duration.
    • Cargo Open Door Message--The chime producer activates the audible warning as requested by the BCM. The BCM sends a serial data message to the chime producer indicating the chime frequency of a medium rate and at a finite duration.
    • Clean Exhaust Filter Message--The chime producer activates the audible warning as requested by the BCM. The BCM sends a serial data message to the chime producer indicating the chime frequency of a medium rate and at a finite duration.
    • Engine Overheated Stop Engine Message--The chime producer activates the audible warning as requested by the BCM. The BCM sends a serial data message to the chime producer indicating the chime frequency of a fast rate and at a continuous duration.
    • Engine Power Is Reduced Message--The chime producer activates the audible warning as requested by the BCM. The BCM sends a serial data message to the chime producer indicating the chime frequency of a medium rate and at a continuous duration.
    • Fuel Level Low Message--The chime producer activates the audible warning as requested by the BCM. The BCM sends a serial message to the chime producer indicating the chime frequency of a fast rate and at a continuous duration.
    • Oil Pressure Indicator--The chime producer activates the audible warning as requested by the BCM. The BCM sends a serial data message to the chime producer indicating the chime frequency of a fast rate and at a continuous duration.
    • Tire Pressure Low Indicator--The chime producer activates the audible warning as requested by the BCM. The BCM sends a serial data message to the chime producer indicating the chime frequency of a fast rate and at a continuous duration.
    • Turn Signal Indicators--The chime producer activates the audible warning as requested by the IPC. The chime produces two different chimes, one when the turn signal turns off and another when the turn signal turns on.
    • Vehicle Dynamics Caution Message--The chime producer activates the audible warning as requested by the BCM. The BCM sends a serial data message to the chime producer indicating the chime frequency of a fast rate and at a continuous duration.
    • Vehicle Overspeed Message--The chime producer activates the audible warning as requested by the BCM. The BCM sends a serial data message to the chime producer indicating the chime frequency of a medium rate and at a finite duration.
    • Transmission Hot Idle Engine Message--The chime producer activates the audible warning as requested by the BCM. The BCM sends a serial data message to the chime producer indicating the chime frequency of a fast rate and at a continuous duration.

Refer to Indicator/Warning Message Description and Operation.