CHIME/BUZZER
DESCRIPTION
A chime warning system is standard factory-installed equipment. The chime warning system uses an electromechanical transducer and an electromechanical relay that are soldered onto the electronic circuit board inside of the ElectroMechanical Instrument Cluster (EMIC) (1) to provide audible indications of various vehicle conditions that may require the attention of the vehicle operator or occupants. The EMIC 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 or CCN.
The electromechanical transducer generates beep tones and chime tones, while the electromechanical relay generates click tones to emulate the sounds associated with conventional turn signal and hazard warning flasher operation. The microprocessor-based EMIC utilizes electronic chime request messages received from other modules in the vehicle over the Controller Area Network (CAN) data bus along with hard wired inputs to monitor many sensors and switches throughout the vehicle. In response to those inputs, the circuitry and programming of the EMIC allow it to control the audible outputs that are produced through its on-board transducer and relay.
The EMIC is capable of producing the following audible outputs:
- Slow Rate Repetitive Click - Repeated click tones that are issued at a slow rate of about 90 clicks per minute.
- Fast Rate Repetitive Click - Repeated click tones that are issued at a fast rate of more than about 180 clicks per minute.
- 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.
Hard wired circuitry connects the EMIC 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 EMIC 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 EMIC chime warning system circuits and components cannot be adjusted or repaired. If the EMIC circuitry, the on-board transducer or the relay are damaged or ineffective, the EMIC unit must be replaced.
OPERATION
The chime warning system operates on battery voltage received through a fuse in the Totally Integrated Power Module (TIPM) on a non-switched fused B(+) circuit so that the system may operate regardless of the ignition switch position. The chime warning system also monitors the ignition switch position so that some chime features are functional only with the ignition switch in the ON position, while others are functional regardless of the ignition switch position.
The chime warning system provides an audible indication to the vehicle operator or occupants under the following conditions:
- Airbag Indicator Warning - The ElectroMechanical Instrument Cluster (EMIC) (also known as the Cab Compartment Node/CCN) transducer will generate one short chime when the ignition switch is in the ON position, and the airbag indicator is illuminated. This warning indicates that a failure condition has been monitored affecting the operation of the Supplemental Restraint System (SRS) related components or circuits. This warning will only occur following completion of the airbag indicator bulb test, and will only occur once during any ignition cycle.
- Door Ajar Warning - The EMIC/CCN will generate one short chime when the ignition switch is in the ON position, when the door ajar indicator is illuminated, or when a DOOR(S) OPEN textual message is displayed in the reconfigurable display of the instrument cluster. This warning indicates that a door is, or multiple doors are not closed or completely latched while the vehicle is moving.
- Fasten Seat Belt Indicator Warning - The EMIC/CCN transducer will generate repetitive chimes at a slow rate to announce that the seat belt switches and the ignition switch indicate that a front seat belt is not fastened with the ignition switch in the ON position. Vehicles with the optional Occupant Classification System (OCS) monitor both outboard front seat belts, while vehicles without OCS monitor only the driver side front seat belt. The chime warning system also supports the enhanced seat belt reminder (beltminder) when this feature is enabled. (Refer to 8 - ELECTRICAL/INSTRUMENT CLUSTER/SEAT BELT INDICATOR - OPERATION).
- Gate Ajar Indicator Warning - The EMIC/CCN transducer will generate one short chime when the liftgate ajar indicator is illuminated, or when a LIFTGATE OPEN textual message is displayed in the reconfigurable display of the instrument cluster. This warning indicates that the liftgate is not closed or completely latched while the vehicle is moving.
- Head/Park Lamps-On Warning - The EMIC/CCN transducer will generate repetitive chimes at a fast rate to indicate that inputs from the headlamp switch and the ignition switch indicate that the exterior lamps are turned ON with the ignition switch in the OFF position, and a hard wired input is received indicating that the driver side front door is open. The chimes will continue to sound until the exterior lamps are turned OFF, the driver side front door is closed, or the ignition switch is turned to the ON position, whichever occurs first.
- Key-In-Ignition Warning - The EMIC/CCN transducer will generate repetitive chimes at a fast rate to indicate that inputs from the key-in ignition switch, the ignition switch, and the driver side front door ajar switch indicate that the key is in the ignition lock cylinder with the ignition switch in the OFF position with the driver side front door open. The chimes will continue to sound until the key is removed from the ignition lock cylinder, the driver side front door is closed, or the ignition switch is turned to the ON position, whichever occurs first.
- Low Fuel Indicator Warning - The EMIC/CCN transducer will generate one short chime when the low fuel indicator is illuminated in the instrument cluster. This warning indicates that the monitored fuel level in the fuel tank is low. This chime will only occur once during any ignition cycle.
- Overspeed Warning - The EMIC transducer will generate one short chime when the vehicle speed is over a pre-programmed speed value. This feature is only enabled on vehicles that have been configured for sale in a Middle East Gulf Coast Country (GCC).
- Park Brake Reminder - The EMIC/CCN transducer will generate one short chime when the brake/park brake indicator is illuminated to announce that the park brake is applied or not fully released and the vehicle is moving. This chime will repeat each time the input conditions are met.
- Sentry Key Customer Learn Mode Announcement - The EMIC/CCN transducer will generate one short chime to confirm that the Sentry Key electronic Customer Learn mode is active, which indicates that the Sentry Key Remote Entry Module/Wireless Control Module (SKREEM/WCM) is prepared for programming additional Sentry Key transponders. This chime feature is only active on vehicles equipped with the optional Sentry Key system, and sold in a market where Customer Learn programming is an allowed feature.
- Turn Signal/Hazard Warning Flasher Emulation - The EMIC/CCN relay will generate repetitive clicks at a slow rate to emulate an electromechanical flasher when the turn signal or hazard warning system are operating. The EMIC/CCN relay will generate repetitive clicks at a fast rate to indicate that the right or left turn signals are operating with one or more bulbs ineffective. In either case, the clicks will continue until the turn signal and hazard warning systems are turned OFF.
- Turn Signal On Warning - The EMIC/CCN transducer will generate repetitive chimes at a slow rate to indicate that a turn signal has been active continuously for 1.6 kilometers (1 mile) with the vehicle speed greater than 22 kilometers-per-hour (15 miles-per hour). Vehicles built for markets other than the United States and Canada have a revised distance threshold of 4 kilometers (2.49 miles) for this feature. The chime will continue until the turn signal input becomes inactive or until the vehicle speed message indicates that the speed is less than 22 kilometers-per-hour (15 miles-per-hour), whichever occurs first. The hazard warning flashers will not activate this chime feature.
- Warning Indicator Announcement - The EMIC/CCN transducer will generate one short chime each time the Malfunction Indicator Lamp (MIL) lamp or certain other indicators are illuminated by the instrument cluster circuitry. The MIL and certain other indicators may be illuminated when any critical engine or transmission systems are operating outside of their normal parameters. The instrument cluster monitors electronic messages received over the CAN data bus to determine when to illuminate these indicators.
The EMIC/CCN provides chime service for all available features in the chime warning system, except for the audible warning function provided by each of the optional park assist system display modules. The EMIC/CCN relies upon its internal programming, numerous hard wired inputs, and electronic message inputs received from other modules over the Controller Area Network (CAN) and the Local Interface Network (LIN) data buses to provide the chime warning system features. The internal programming of the EMIC/CCN determines the priority of each chime request input that is received, as well as the rate and duration of each chime that is to be generated.
The hard wired circuits between components related to the chime warning system may be diagnosed using conventional diagnostic tools and procedures. Refer to the appropriate wiring information. The wiring information includes wiring diagrams, proper wire and connector repair procedures, details of wire harness routing and retention, connector pin-out information and location views for the various wire harness connectors, splices and grounds.
However, conventional diagnostic methods will not prove conclusive in the diagnosis of the chime warning system or the electronic controls or communication between modules and other devices that provide some features of the chime warning system. The most reliable, efficient, and accurate means to diagnose the chime warning system or the electronic controls and communication related to chime warning system operation requires the use of a diagnostic scan tool. Refer to the appropriate diagnostic information.