The audible warnings alert the driver of a system concern or a critical vehicle condition. The radio generates the audible warnings through a speaker. The radio receives audible warning requests from the body control module (BCM) via the GMLAN serial data
line. If the radio receives multiple audible warning requests, the warning with the highest priority sounds first. The following lists the audible warning priority and the pulse rate:
| • | Fast rate chime (200 pulses per minute) |
| • | Medium rate chime (150 pulses per minute) |
| • | Slow rate chime (50 pulses per minute) |
Fasten Safety Belt Warning
The radio activates the fasten safety belt audible warning as requested by the body control module (BCM). The BCM sends a GMLAN message to the radio indicating the chime frequency (slow rate) and duration (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 BCM detects that the driver seat belt is not buckled (signal circuit is low). The radio receives a GMLAN 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.
Key-In-Ignition Warning
The radio activates the key-in-ignition audible warning as requested by the body control module (BCM). The BCM sends a GMLAN message to the radio indicating the chime frequency (medium rate) and duration (continuous). The key-in-ignition warning sounds
when the following occurs:
| • | The ignition switch is OFF. |
| • | The BCM determines that the driver door is open (signal circuit is low). |
| • | The BCM determines that the ignition key alarm switch is closed (signal circuit is low). |
Lights On Warning
The radio activates the lights on warning as requested by the body control module (BCM). The BCM sends a GMLAN message to the radio indicating the chime frequency (fast rate) and duration (continuous). The lights on warning sounds when the following occurs:
| • | The BCM determines that the driver door is open (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 body control module (BCM). The BCM sends a GMLAN message to the radio indicating the chime frequency (fast rate) and duration (continuous). The park brake warning sounds and the brake
indicator illuminates when the following occurs:
| • | The vehicle speed is greater than 5 km/h (3.1 mph). The BCM receives a GMLAN message from the engine control module (ECM) indicating the vehicle speed. |
| • | The BCM determines that the park brake is engaged (signal circuit is low). |
Turn Signal On Warning
The instrument panel cluster (IPC) activates the turn signal audible warning as requested by the body control module (BCM). The BCM sends a GMLAN message to the IPC indicating the chime frequency (single chime in phase with turn signal indicator) and duration
(continuous). The turn signal on warning sounds when the following occurs:
| • | The BCM detects that the turn signal is active for greater than 1.2 km (0.75 mi). The BCM calculates the distance based on a class 2 message from the engine control module (ECM) indicating the vehicle speed. |
Additional Warnings
The following warnings have an associated instrument panel cluster (IPC) indicator:
| • | High Engine Coolant Temperature |
| • | Low Engine Oil Pressure |
The body control module (BCM) sends a GMLAN message to the radio indicating the chime frequency (medium rate) and duration (3 seconds). The warning sounds once per ignition cycle when an indicator illuminates and the engine is running for greater
than 6.5 seconds.
For a description of each indicator, refer to
Indicator/Warning Message Description and Operation
.
