Jeep 1997 Grand Cherokee Service Manual page 599

ZG
DIAGNOSIS AND TESTING (Continued)
DRIVER SEAT BELT SWITCH
For circuit descriptions and diagrams, refer to
8W-45 - Body Control Module in Group 8W - Wiring
Diagrams.
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, REFER TO
RESTRAINT SYSTEMS BEFORE ATTEMPTING ANY
STEERING WHEEL,
INSTRUMENT PANEL COMPONENT DIAGNOSIS OR
SERVICE. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Disconnect and isolate the battery negative
cable. Unplug the driver seat belt switch wire har-
ness connector from the driver seat belt retractor
behind the B pillar trim. Check for continuity
between the seat belt switch sense circuit and the
ground circuit cavities of the seat belt retractor half
of the driver seat belt switch wire harness connector.
There should be continuity with the seat belt web-
bing retracted, and no continuity with the seat belt
webbing extracted far enough to buckle the seat belt.
If OK, go to Step 2. If not OK, replace the faulty seat
belt tip-half and retractor assembly.
(2) Check for continuity between the ground cir-
cuit cavity in the body half of the driver seat belt
switch wire harness connector and a good ground.
There should be continuity. If OK, go to Step 3. If not
OK, repair the circuit to ground as required.
(3) Unplug the black 14-way wire harness connec-
tor from the Body Control Module (BCM). Check for
continuity between the seat belt switch sense circuit
cavity in the body half of the driver seat belt switch
wire harness connector and a good ground. There
should be no continuity. If OK, go to Step 4. If not
OK, repair the short circuit as required.
(4) Check for continuity between the seat belt
switch sense circuit cavities in the body half of the
driver seat belt switch wire harness connector and
the 14-way BCM wire harness connector. There
should be continuity. If OK, use a DRB scan tool and
the proper Diagnostic Procedures manual to test the
BCM. If not OK, repair the open circuit as required.
KEY-IN IGNITION SWITCH
For circuit descriptions and diagrams, refer to
8W-40 - Instrument Cluster or 8W-44 - Interior
Lighting in Group 8W - Wiring Diagrams.
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, REFER TO
RESTRAINT SYSTEMS BEFORE ATTEMPTING ANY
STEERING WHEEL,
INSTRUMENT PANEL COMPONENT DIAGNOSIS OR
GROUP 8M - PASSIVE
STEERING COLUMN,
GROUP 8M - PASSIVE
STEERING COLUMN,
CHIME/BUZZER WARNING SYSTEMS
SERVICE. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Disconnect and isolate the battery negative
cable. Remove the steering column shrouds. Refer to
Group 8D - Ignition Systems for the procedures.
Unplug the key-in ignition switch wire harness con-
OR
nector from the ignition switch.
(2) Check for continuity between the key-in igni-
tion switch sense and ground terminals of the key-in
ignition switch. There should be continuity with the
key in the ignition lock cylinder, and no continuity
with the key removed from the ignition lock cylinder.
If OK, go to Step 3. If not OK, replace the faulty igni-
tion switch assembly.
(3) Check for continuity between the ground cir-
cuit cavity of the key-in ignition switch wire harness
connector and a good ground. There should be conti-
nuity. If OK, go to Step 4. If not OK, repair the open
circuit to ground as required.
(4) Unplug the black 24-way wire harness connec-
tor from the Body Control Module (BCM). Refer to
Group 8E - Instrument Panel Systems for the proce-
dures. Check for continuity between the key-in igni-
tion switch sense circuit cavity of the key-in ignition
switch wire harness connector and a good ground.
There should be no continuity. If OK, go to Step 5. If
not OK, repair the short circuit as required.
(5) Check for continuity between the key-in igni-
tion switch sense circuit cavities of the key-in igni-
tion switch wire harness connector and the black
24-way BCM wire harness connector. There should
be continuity. If OK, use a DRB scan tool and the
proper Diagnostic Procedures manual to test the
BCM. If not OK, repair the open circuit as required.
HEADLAMP SWITCH
If the park lamps are inoperative, refer to Group
8L - Lamps for diagnosis. If the park lamps operate,
but there is no chime warning issued with the driver
side front door open, proceed as follows. For circuit
descriptions and diagrams, refer to 8W-40 - Instru-
ment Cluster or 8W-44 - Interior Lighting in Group
8W - Wiring Diagrams.
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, REFER
RESTRAINT SYSTEMS BEFORE ATTEMPTING ANY
STEERING WHEEL,
INSTRUMENT PANEL COMPONENT DIAGNOSIS OR
SERVICE. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
OR INJURY.
TO GROUP 8M -
STEERING COLUMN,
8U - 3
PASSIVE
OR