Grand Cherokee 4WD Laredo V8-4.7L (2002)
Horn Switch: Testing and Inspection
For complete circuit diagrams, 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.
WARNING: ON VEHICLES EQUIPPED WITH AIRBAGS, REFER TO ELECTRICAL, RESTRAINTS BEFORE ATTEMPTING ANY
STEERING WHEEL, STEERING COLUMN, OR INSTRUMENT PANEL COMPONENT DIAGNOSIS OR SERVICE. FAILURE TO TAKE
THE PROPER PRECAUTIONS COULD RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL INJURY.
1. Disconnect and isolate the battery negative cable. Remove the steering column opening cover from the instrument panel.
2. Check for continuity between the metal steering column jacket and a good ground. There should be continuity. If OK, go to Step 3. If not OK,
refer to Steering, Column for proper installation of the steering column.
3. Remove the driver side airbag module from the steering wheel. Disconnect the horn switch wire harness connectors from the driver side airbag
module.
4. Remove the horn relay from the Power Distribution Center (PDC). Check for continuity between the steering column half of the horn switch feed
wire harness connector and a good ground. There should be no continuity. If OK, go to Step 5. If not OK, repair the shorted horn relay control
circuit to the horn relay in the PDC as required.
5. Check for continuity between the steering column half of the horn switch feed wire harness connector and the horn relay control circuit cavity for
the horn relay in the PDC. There should be continuity. If OK, go to Step 6. If not OK, repair the open horn relay control circuit to the horn relay in
the PDC as required.
6. Check for continuity between the horn switch feed wire and the horn switch ground wire on the driver side airbag module. There should be no
continuity If OK, go to Step 7. If not OK, replace the faulty horn switch.
7. Depress the center of the driver side airbag module trim cover and check for continuity between the horn switch feed wire and the horn switch
ground wire on the driver side airbag module. There should now be continuity If not OK, replace the faulty horn switch.
