Principles of Operation

PRINCIPLES OF OPERATION

The instrument cluster controls the following warnings and chimes:
- driver safety belt not fastened warning chime (warning times out)
- key-in-ignition warning (repetitive chime)
- headlamp on warning (repetitive chime)
- turn signal reminder (repetitive chime)
- air bag warning chime (repetitive chime)
- fail-safe cooling warning chime (repetitive chime)
- belt minder warning chime (repetitive chime after a delay and the seat belt chime has completed)

Safety Belt Warning Chime
The safety belt warning chime, along with the safety belt warning lamp, provides both an auditory and visual warning that the safety belt is not fastened. The safety belt warning lamp illuminates and the chime sounds when the driver safety belt is not fastened and the key is turned from the OFF/LOCK or ACC to the RUN position. The safety belt warning lamp stops illuminating and the chime stops sounding when the safety belt is fastened, when the key is switched from the RUN to the OFF/LOCK or ACC position, or when the chime has sounded for approximately 6 seconds.

The safety belt warning chime inputs are:
- key in START position
- key in RUN position
- driver or passenger safety belt switch inputs buckle position to the instrument cluster on circuit 8-GE52 (WH/BK)

Safety Belt Minder
The belt minder feature supplements the initial safety belt warning function to provide an extended warning. The belt minder is enabled after the current safety belt warning is complete. The belt minder reminds the driver that the driver safety belt is unbuckled by intermittently sounding a chime and illuminating the safety belt warning lamp in the instrument cluster. While activated, the belt minder alternates the chime and indicator from on for 6 seconds to off for 30 seconds for a period of 5 minutes or until the safety belt is fastened.

NOTE: The belt minder is configurable. To configure without using a diagnostic tool, refer to Belt Minder Deactivating/Activating.

Key-In-Ignition Warning Chime
The key-in-ignition warning chime warns that the key is still in the ignition when the driver door is ajar. The key-in-ignition warning chime sounds when the driver door is ajar, the key is in the ignition in the OFF/LOCK, START/RUN or ACC position. The key-in-ignition warning chime stops sounding when the driver door is closed or if the key is removed from the ignition.

The key-in-ignition warning chime input is received through circuit 30S-GM7 (RD/WH). Voltage is applied with the key in the ignition switch.

Headlamp On Reminder Chime
The headlamp on reminder chime is used to alert the driver that the headlamps are on when the driver door is ajar and the key is out of the ignition. The headlamps on reminder chime sounds if the driver door is ajar, the headlamp switch is in the PARK or HEADLAMP position, and the key is in the OFF/LOCK position with the key out. The headlamp on reminder chime stops sounding when any one of the above conditions are removed.

The headlamp on warning chime inputs are:
- ignition switch position
- headlamp switch position
- door ajar switch position

Air Bag Warning Chime
The air bag warning chime is used as a redundant warning in conjunction with the air bag warning indicator. If the air bag warning indicator in inoperative, the instrument cluster then provides an audible chime to alert the driver that the supplemental restraint system is in need of repair.

Fail-Safe Cooling Warning Chime
The fail-safe cooling mode has 2 levels of operation, which are transmitted from the powertrain control module (PCM) over the communication network to the instrument cluster. When the engine coolant temperature reaches an over-temperature condition, the PCM provides a level 1 over-temperature signal to the instrument cluster. The instrument cluster positions the temperature gauge in the HOT range, illuminates the over-temperature warning indicator, oil pressure warning indicator, and malfunction indicator lamp (MIL). The instrument cluster also provides an intermittent chime, consisting of 3 tones within a 2-second interval. If the over-temperature continues to increase, the PCM provides the instrument cluster with a level 2 over-temperature signal and the intermittent chime strategy sounds 5 tones within a 2-second interval.

Turn Signal Reminder Chime
The turn signal reminder chime alerts the driver that the turn signals are still on. If the turn signals are placed in the RH or LH position and the vehicle has traveled approximately 0.8 kilometers (0.5 miles) the instrument cluster provides an audible chime.