ZJ CHIME/BUZZER WARNING SYSTEMS 8U - 1 CHIME/BUZZER WARNING SYSTEMS CONTENTS page pageDIAGNOSIS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 SERVICE PROCEDURES ................... 5GENERAL INFORMATION . . . . . . . . . . . . . . . . . . 1 GENERAL INFORMATION This group covers the standard equipment chime The chime module can not be repaired. If faulty, itwarning system on Grand Cherokee models. The sys- must be replaced.tem provides an audible warning to the driver whenit monitors the following conditions:• key is in ignition switch with the driver’s dooropen (On some vehicles, a warning will not sound ifthe ignition switch is in the ON position when theleft front door is open)• exterior lamps are ON when the ignition switch isOFF, key is removed from ignition lock cylinder, andleft front door is open• driver’s seat belt is not buckled with ignitionswitch in ON position• an input from the vehicle information center is re-ceived. There is also a power door lock inhibit feature onvehicles with the chime module. If the key is in theignition lock cylinder or exterior lamps are ON, whilethe left front door is open, the power lock/keyless en- Fig. 1 Chime Module Locationtry systems will not operate. Following are general descriptions of the majorcomponents in the chime warning system. Refer toGroup 8W - Wiring Diagrams for complete circuit de-scriptions and diagrams.CHIME MODULE The chime module is located on a bracket underthe left end of the instrument panel (Figs. 1 and 2).It receives battery voltage at all times from fuse 8 inthe fuseblock module. It also receives a second bat-tery feed through fuse 9 when the ignition switch isin the ON or START position. Other inputs to the module include the driver’sdoor jamb switch, the driver’s seat belt switch, the ig-nition key-in switch, the headlamp switch, and thetone line from the vehicle information center (if Fig. 2 Chime Module and Connectorequipped). The only output of the module is a timed4 to 8 second feed to the seat belt reminder lamp in DRIVER’S DOOR JAMB SWITCHthe message center of the instrument cluster. The The driver’s door jamb switch is mounted to thetimer function begins after the ignition switch is driver’s door hinge pillar. The switch closes a path toturned to the ON position. ground for the chime module through the key-in
8U - 2 CHIME/BUZZER WARNING SYSTEMS ZJswitch or headlamp switch when the driver’s door is mally closed, providing a ground path to the chimeopened, and opens when the driver’s door is closed. module. When the tip-half of the seat belt is insertedThis switch can not be repaired. If faulty, it must be into the seat belt buckle, the switch opens the chimereplaced. module ground path. The seat belt switch can not be repaired. If faulty, the entire driver’s seat belt buck-IGNITION KEY-IN SWITCH le-half must be replaced. Refer to Group 23 - Body The key-in switch is integral to the ignition switch, Components for service procedures.which is mounted on the right side of the steeringcolumn. It closes a path to ground for the chime mod- VEHICLE INFORMATION CENTER TONE LINEule when the ignition key is inserted in the ignition If the vehicle is equipped with the optional Vehiclelock cylinder and the driver’s door jamb switch is Information Center (VIC), an output from the VICclosed (door open). The switch opens when the key is provides a ground signal to the chime module whenremoved from the ignition lock cylinder. This switch it detects a fault. This signal causes the chime mod-can not be repaired. If faulty, the entire ignition ule to sound an audible signal to the driver. Refer toswitch must be replaced. Refer to Group 8D - Igni- Group 8E - Instrument Panel and Gauges for moretion Systems for service procedures. information on the VIC system.HEADLAMP SWITCH The headlamp switch is located in the instrument POWER DOOR LOCK INHIBITpanel. It closes a path to ground for the chime mod- Pin 8 of the chime module provides the ground forule when the park or headlamps are on and the driv- the coil side of the power door lock relay. The LOCKer’s door jamb switch is closed (door open). The function will not operate if:switch opens the ground path when the park and • the chime module is not plugged inheadlamps are turned off. The headlamp switch can • the key is in the ignition lock cylinder, or exteriornot be repaired. If faulty, it must be replaced. Refer lamps are ON, while the left front door is opento Group 8E - Instrument Panel and Gauges for ser- • the power door lock inhibit feature of the chimevice procedures. module is inoperable due to defective electronics in the chime module. (In this case, the power door lockDRIVER’S SEAT BELT SWITCH operation is unpredictable.) The driver’s seat belt switch is integral to the driv-er’s seat belt buckle-half assembly. The switch is nor-
ZJ CHIME/BUZZER WARNING SYSTEMS 8U - 3 DIAGNOSISCHIME WARNING SYSTEM If the chime module does not operate as described,check the two fuses for pins 1 and 7 (Figs. 3, 4) andreplace as required. If the fuses are not defective,perform the following tests to determine if the prob-lem is in the module or in the wiring. (1) Remove the module and replace with a knowngood module. Now, check operation again. If the prob-lem is not corrected by replacing the module, re-in-stall original module and go to next step. Fig. 4 Chime Module Terminal Identification filament). If OK, go to next step. If not OK, repair circuit to seat belt warning lamp or replace bulb as required. (5) Check resistance between chime module con- nector pin 3 and a good ground. Meter should read zero ohms. If OK, go to next step. If not OK, repair circuit to ground as required. (6) Check resistance between chime module con- nector pin 4 and a good ground. Meter should read zero ohms with left front seat belt unbuckled and Fig. 3 Chime Module Connector Terminal open circuit with belt buckled. If OK, go to next step. Identification If not OK, repair circuit to seat belt switch or replace seat belt buckle half as required. (2) Turn ignition switch to ON position. Measure (7) Open left front door. Check resistance betweenvoltage at chime module connector pin 1. Meter chime module connector pin 6 and a good ground.should read battery voltage. If OK, go to next step. If Meter should read open circuit. Insert key ignitionnot OK, repair circuit to ignition switch as required. lock cylinder and meter should read zero ohms. If (3) Turn ignition switch to OFF and remove key OK, go to next step. If not OK, repair circuit to key-from ignition lock cylinder. Measure voltage at chime in-ignition switch or replace key-in ignition switch asmodule connector pin 7. Meter should read battery required.voltage. If OK, go to next step. If not OK, repair cir- (8) Remove key from ignition lock cylinder. Opencuit to fuseblock module as required. left front door and turn headlamp switch ON. Check (4) Turn ignition switch to OFF position. Discon- resistance between chime module connector pin 6nect battery negative cable. Check resistance be- and a good ground. Meter should read zero ohms. Iftween chime module connector pin 2 and a good OK, replace faulty chime module. If not OK, repair circuit to headlamp switch or replace headlampground. Meter should read almost zero ohms (bulb switch as required.
ZJ CHIME/BUZZER WARNING SYSTEMS 8U - 5 Fig. 6 Halo Lamp And Key-In-Ignition Switch Continuity Chart SERVICE PROCEDURES Service procedures for components of the chime • headlamp switch - refer to Group 8E - Instrumentwarning system can be found in the appropriate Panel and Gaugesgroup as follows: • driver’s seat belt switch - refer to Group 23 - Body• driver’s door jamb switch - refer to Group 8L - Components.Lamps• ignition key-in switch - refer to Group 8D - Igni-tion Systems