Audible Warning Device: Description and Operation

GENERAL INFORMATION INTRODUCTION
The chime system provides the driver with warning chimes for:
- Seat Belt
- Exterior Lamps ON
- Key-In Ignition
- Tire Pressure
- Dome Lamp ON
- Warning Lamp Announcement
- Turn Signal On

The Chime Warning/Reminder System can be diagnosed using a scan tool (DRB). Refer to the proper Body Diagnostic Procedures for testing procedures and scan tool usage instructions.

CHIME SYSTEMS
The Chime System is an integral part of the Body Control Module (BCM) and provides the driver with two types of chimes, Warning and Announcement. The BCM monitors its hardwired inputs and CCD bus messages to determine when a chime is needed. The Warning Chimes are a dual tone chime for the following conditions: Seat Belt Unbuckled, Exterior Lamps On, Key-In Ignition, Critical tire pressure, and Dome Lamps On. The Announcement Chime is a single tone chime to warn the driver when an instrument cluster gauge is out of range or a warning lamp is on. Refer to the General Information System Description and Functional Operation for more information on the Instrument Cluster gauges and warning lamps.

During shipment (with the IOD fuse disconnected) the Warning and Announcement chimes will not work with the ignition key turned off.

SEAT BELT CHIME
The seat belt chime will sound for 4 to 8 seconds, when the ignition is turned on and the driver's seat belt is not buckled (seat belt switch is closed to ground). This is a reminder to the driver to buckle the seat belt. The seat belt lamp is controlled by the BCM via the CCD bus. The cluster will illuminate the seat belt warning lamp for 6 seconds. Buckling the Driver's seat belt before the time out has expired will cause the chime to stop immediately.

Chime rate: 38 to 62 chimes per minute.

To test the seat belt warning system, start with the ignition switch in the OFF position. Turn the ignition switch to the ON position with the driver's seat belt not buckled. The seat belt warning lamp should light and the chime should sound 4 to 8 seconds.

SEAT BELT LAMP
The seat belt lamp in the instrument cluster signals the driver's to fasten the seat belt. The seat belt lamp is illuminated for 6 seconds after the instrument cluster receives the message from the Body Control Module. The seat belt lamp is therefore illuminated for 6 seconds whenever the ignition switch is moved to run/start position. While ignition is off, the seat belt lamp will not be illuminated. This lamp will be illuminated for 6 seconds with every run/start cycle of the ignition switch.

Chime rate: 50±12 chimes per minute.

EXTERIOR LAMPS ON CHIME
The exterior lamp on chime will warn the driver that the exterior lights have been left on.

With the ignition switch OFF:
- Driver's door is open (door ajar switch is closed to ground)
- Parking lamps or headlamps ON (parking lamp switch is closed to ground)

The chime will sound until lights are turned OFF, driver's door closed or until the battery protection time out of 3 minutes has expired.

Chime rate: 168 to 192 chimes per minute.

To test the exterior lamps left on function:
- Turn ignition off
- Remove ignition key
- Turn exterior lamps on with driver's door open. Chime should sound until lamps are turned off or driver's door is closed.

KEY-IN IGNITION CHIME
The key-in ignition chime will act as a warning to the driver that the ignition key has been left in the ignition switch.

With the ignition switch is in the OFF position ONLY:
- Driver's door is open/ajar (door ajar switch is closed to ground)
- Key is in the ignition switch (key-in ignition switch is closed to ground)

The chime will sound until one of the above conditions is removed or the battery' protection timeout of 15 minutes has expired.

Chime rate: 168 to 192 chimes per minute.

To test the key-in ignition function, insert key into the ignition and open Driver's door. Do not turn ignition ON. Chime should sound until key is removed from ignition or Driver's door is closed.

DOME LAMP OR COURTESY LAMP ON CHIME
The dome lamp on chime Will warn the driver that the dome lamps have been left on.

When the ignition is OFF:
- Driver's door OPEN (door ajar switch is closed to ground
- Dome lamps are ON (dome lamp switch is closed to ground),

The chime will sound continuously until Driver's door is closed, dome lamps tuned OFF or until the battery protection time out of 15 minutes has expired.

Chime rate: 168 to 192 chimes per minute.

WARNING LAMP ANNOUNCEMENT CHIME
The warning lamp announcement chime will warn the driver to scan the instrument cluster to observe the gauges and lamp indicators. Whenever the check gauge, low fuel, low washer fluid level, door/check lid ajar, low tire pressure, low oil pressure, airbag warning, or service engine soon lamps are first illuminated, the chime will sound one tone. The door/deck lid ajar warning lamp announcement chime sounds only if the vehicle speed is above 2 m.p.h.

NOTE The Door and Decklid Ajar Lamps are located in the odometer for 1999.

The low tire pressure critical chime will sound with each flash of the low tire warning lamp. The door and trunk ajar warning lamp announcement chime is only given if the vehicle speed is above 2 miles per hour.

Two seconds after ignition switch is turned ON or until the seat belt warning chime ends, multiple warning announcement chimes will be consolidated into one warning announcement. This will occur 2 seconds after the seat belt warning chime ends.

If a warning announcement should occur while a higher priority warning chime is in process, no additional warning lamp announcement chime will be given after the chime in process ends. All associated lamps will illuminate and the active chime will serve as the warning announcement.

In the case of the chime warning associated with the Service Engine Soon lamp, the chime will sound only the first illumination of this lamp. Any other condition that could normally activate the warning announcement associated with the service engine soon lamp will not reactivate the chime if the lamp is currently illuminated.

NOTE: If the CCD bus communication with the engine controller is lost, the BCM assumes a vehicle speed of 3 MPH. This results in the door ajar warning tone being sounded immediately whenever a door or trunk becomes ajar.

TURN SIGNAL ON CHIME
The Turn Signal On Chime will act as a warning to the driver that the turn signals have been left on. When a level change is detected on the turn signal inputs to the BCM continuously for approximately 1 mile, and the vehicle speed is greater than 15 MPH, the chime will sound continuously until the turn signal inputs are no longer active. If vehicle speed drops below 15 MPH prior to the warning being activated the accumulated distance traveled will be reset. Chime rate is approximately 50 chimes per minute.

AIRBAG WARNING LAMP ANNOUNCEMENT CHIME
The Airbag Warning Lamp is monitored by the BCM. If the engine exceeds 450 RPM for more than 10 seconds and the airbag warning lamp is on, a single chime will be sounded. The chime will not be rearmed until the vehicle speed equals zero and the Airbag Warning Lamp is off.

ENGINE TEMPERATURE HIGH AND CRITICAL CHIME
The engine temperature high and critical chime will warn the driver that the engine is overheating. While monitoring the coolant temperature, the Powertrain Control Module (PCM) will send on the CCD bus as engine temperature every 1.376 seconds to the Body Control Module (BCM). The BCM calculates engine temperature and determines if a warning should occur. This feature is functional only with the Ignition Switch in the Run/Start position.

When the engine temperature reaches HIGH temperature of 121C (250F) the BCM will chime one tone and the engine temperature lamp comes ON. The BCM turns OFF the lamp when the engine temperature reaches 117°C (242°F). The BCM will chime a second warning when the engine temperature reaches CRITICAL temperature of 125°C (257°F).

LOW OIL PRESSURE CHIME
The engine low oil pressure chime will warn the driver that the vehicle's engine oil pressure is low. The oil pressure switch, which will close to ground during a low oil pressure condition, will directly illuminate the check engine lamp located in the message center. The BCM will monitor the oil pressure switch and signal a low oil pressure condition with one warning chime when the following conditions are met:

1. Ignition switch is in the ON position
2. Engine running, indicated by RPM above 1,500±30 for 10 seconds.
3. Oil pressure switch closed to ground for one second minimum to two seconds maximum