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Chime Warning System






CHIME WARNING SYSTEM





A chime warning system is standard factory-installed equipment. The chime warning system uses an electromechanical transducer attached to the electronic circuit board inside of the instrument cluster (1) to provide audible indications of various vehicle conditions that may require the attention of the vehicle operator or occupants. The instrument cluster also includes the hardware and software necessary to serve as the electronic body control module and is sometimes referred to as the Cab Compartment Node (CCN).

The electromechanical transducer generates beep tones, chime tones and click tones to emulate the sounds associated with conventional turn signal and hazard warning flasher operation. The microprocessor-based instrument cluster utilizes electronic chime request messages received from other modules in the vehicle over the Controller Area Network (CAN) data bus along with hardwired inputs to monitor many sensors and switches throughout the vehicle. In response to those inputs, the circuitry and programming of the CCN allow it to control the audible outputs that are produced through its on-board transducer.

The CCN is capable of producing the following audible outputs:

- Slow Rate Repetitive Click - Repeated click tones that are issued at a slow rate of about 50 clicks per minute.
- Fast Rate Repetitive Click - Repeated click tones that are issued at a fast rate of more than about 100 clicks per minute.
- Fixed Duration Beep - A short, sharp, single tactile beep tone.
- Single Chime Tone - A single chime tone.
- Slow Rate Repetitive Chime - Repeated chime tones that are issued at a slow rate of about 50 chimes per minute.
- Fast Rate Repetitive Chime - Repeated chime tones that are issued at a fast rate of about 180 chimes per minute.

Hardwired circuitry connects the CCN and the various chime warning system switch and sensor inputs to their modules and to each other through the electrical system of the vehicle. These hard wired circuits are integral to several wire harnesses, which are routed throughout the vehicle and retained by many different methods. These circuits may be connected to each other, to the vehicle electrical system and to the CCN through the use of a combination of soldered splices, splice block connectors, and many different types of wire harness terminal connectors and insulators. Refer to the appropriate wiring information. The wiring information includes wiring diagrams, proper wire and connector repair procedures, further details on wire harness routing and retention, as well as pin-out and location views for the various wire harness connectors, splices and grounds.

The instrument cluster chime warning system circuits and components cannot be adjusted or repaired. If the CCN circuitry or the on-board transducer are damaged or inoperative, the complete unit must be replaced.