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Warning Chimes


The Tone Generator will produce warning chimes if the lights are left "ON," the key is left in the Ignition Switch, or if the driver's seat belt is unfastened.

Power for the Tone Generator is supplied through the LCD Fuse and is hot at all times. The Tone Generator emits three different chime rates which are controlled by the Central Control Module (CCM). The CCM controls the chimes by grounding the chime 1 or chime 2 inputs, or both inputs, at the Tone Generator. The chime rates are shown below:

^ FASTEN SEAT BELT and TURN SIGNAL WARNING - slow
^ KEY-IN-IGNITION WARNING - medium
^ LIGHTS "ON" WARNING - fastest

Each warning function is described starting below:


FASTEN SEAT BELT WARNING

The Fasten Seat Belt Warning Chime is activated when the driver's seat belt is unfastened, and the Ignition Switch is in "RUN," "BULB TEST" or "START."

With the driver's seat belt unfastened, the Seat Belt Switch allows a ground signal to be present at the Seat Belt Input of the Central Control Module (CCM). The CCM will sense this ground, and will then ground the chime 1 input of the Tone Generator. The Tone Generator will chime for approximately 6 seconds if the driver's seat belt remains unfastened.

At the same time the CCM will illuminate the Fasten Seat Belt Indicator by grounding one side of the indicator bulb.


TURN SIGNAL WARNING

The Turn Signal Warning Chime is activated when the Turn Signal has been left "ON" and the vehicle has been driven approximately one mile. The chime is the same as the Fasten Seat Belt Warning (chime 1). The chime will remain "ON" until the Turn Signal has been turned "OFF."

The Central Control Module (CCM) monitors the Turn Signal Flasher input from the Turn Flasher to know when the Turn Signals have been activated. At the same time, the CCM monitors the 4 k/mile Speed Pulse input to calculate when one mile has been driven, thus activating chime 1.

KEY-IN-IGNITION WARNING

The Key-In-Ignition Warning Chime is activated when the Ignition Key is in the Ignition Switch with Ignition "OFF," and the driver's door is open or ajar.

When the key is in the Ignition Switch, the Key-In-Ignition Switch is closed, allowing ground to be present at the Key-In-Ignition input of the Central Control Module (CCM). When the driver's door is open or ajar, the LH Door Ajar Switch allows ground to be present at the LH Door Ajar Input of the CCM. When both of these ground signals are present at the CCM, the CCM will ground the chime input of the Tone Generator enabling the chime. The Tone Generator will chime as long as the above conditions exist.


LIGHTS "ON" WARNING

The Lights "ON" Warning Chime is activated when the Headlamps/Park Lamps are "ON," and the Ignition Key is out of the Ignition Switch. The Central Control Module (CCM) senses battery voltage at the Headlamp/Park Lamp "ON" input if the Headlamps or Park Lamps are "ON." The CCM also senses the absence of ground at the Key-In-Ignition input (no ground with key removed). When both conditions exist, the CCM will ground both the chime 1 and chime 2 inputs of the Tone Generator and activate the chime. The Tone Generator will chime as long as the described conditions exist.