Airbag Indicator Lamp; Anti-Lock Brake System Lamp - Jeep 1997 Grand Cherokee Service Manual

8E - 12 INSTRUMENT PANEL SYSTEMS
DIAGNOSIS AND TESTING (Continued)
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, REFER TO GROUP 8M - PASSIVE RESTRAINT
SYSTEMS BEFORE ATTEMPTING STEERING WHEEL,
STEERING COLUMN, OR INSTRUMENT PANEL COM-
PONENT DIAGNOSIS OR SERVICE. FAILURE TO
TAKE THE PROPER PRECAUTIONS COULD RESULT
IN ACCIDENTAL AIRBAG DEPLOYMENT AND POSSI-
BLE PERSONAL INJURY.
Diagnosis of the system voltage input circuit or the
Powertrain Control Module (PCM) should be per-
formed with the DRB scan tool as described in the
proper Powertrain Diagnostic Procedures manual.
Diagnosis of the voltmeter gauge, the instrument
cluster circuitry, or the CCD data bus should be per-
formed with the DRB scan tool as described in the
proper Body Diagnostic Procedures manual.

AIRBAG INDICATOR LAMP

The diagnosis found here addresses an inoperative
lamp condition. If the airbag indicator lamp stays on
with the ignition switch in the On position, or comes
on and stays on while driving, refer to Group 8M -
Passive Restraint Systems for diagnosis. For circuit
descriptions and diagrams, refer to 8W-40 - Instru-
ment Cluster, 8W-43 - Airbag System, and 8W-45 -
Body Control Module in Group 8W - Wiring Dia-
grams.
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, REFER TO GROUP 8M - PASSIVE RESTRAINT
SYSTEMS BEFORE ATTEMPTING STEERING WHEEL,
STEERING COLUMN, OR INSTRUMENT PANEL COM-
PONENT DIAGNOSIS OR SERVICE. FAILURE TO
TAKE THE PROPER PRECAUTIONS COULD RESULT
IN ACCIDENTAL AIRBAG DEPLOYMENT AND POSSI-
BLE PERSONAL INJURY.
The airbag indicator lamp has a lamp backup fea-
ture. Following the seat belt reminder lamp display
function, if the instrument cluster circuitry has
detected an inoperative airbag warning lamp circuit
it will flash the seat belt reminder lamp on and off
for twenty seconds. Once the instrument cluster cir-
cuitry has detected an inoperative airbag warning
lamp circuit, if a lamp-on message is received from
the Airbag Control Module (ACM) on the CCD data
bus, the seatbelt reminder lamp will flash for twelve
seconds or the duration of the airbag system mal-
function, whichever is longer.
If the airbag indicator lamp fails to light when the
ignition switch is turned to the On position, and the
seat belt reminder lamp flashes following its normal
display function (about seven seconds after the igni-
tion switch is turned to the On position), replace the
airbag indicator lamp bulb with a known good unit.
If the airbag indicator lamp still fails to operate,
diagnosis of the lamp, the instrument cluster cir-
cuitry, the CCD data bus, and the Body Control Mod-
ule (BCM) should be performed with a DRB scan tool
as described in the proper Body Diagnostic Proce-
dures manual.

ANTI-LOCK BRAKE SYSTEM LAMP

The diagnosis found here addresses an inoperative
Anti-lock Brake System (ABS) lamp condition. If the
ABS lamp stays on with the ignition switch in the
On position, or comes on and stays on while driving,
refer to Group 5 - Brakes for diagnosis. If no ABS
problem is found, the following procedure will help
locate a short or open in the ABS lamp circuit. For
circuit descriptions and diagrams, refer to 8W-40 -
Instrument Cluster, and 8W-35 - All-Wheel Anti-Lock
Brakes in Group 8W - Wiring Diagrams.
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, REFER TO GROUP 8M - PASSIVE RESTRAINT
SYSTEMS BEFORE ATTEMPTING STEERING WHEEL,
STEERING COLUMN, OR INSTRUMENT PANEL COM-
PONENT DIAGNOSIS OR SERVICE. FAILURE TO
TAKE THE PROPER PRECAUTIONS COULD RESULT
IN ACCIDENTAL AIRBAG DEPLOYMENT AND POSSI-
BLE PERSONAL INJURY.
(1) Check the fuse in the junction block. If OK, go
to Step 2. If not OK, replace the faulty fuse.
(2) With the ignition switch in the On position,
check for battery voltage at the fuse in the junction
block. If OK, go to Step 3. If not OK, repair the open
circuit to the ignition switch as required.
(3) Disconnect and isolate the battery negative
cable. Remove the instrument cluster bezel and the
cluster assembly.
(4) Connect the battery negative cable. Check for
battery voltage between the fused ignition switch
output circuit and the ABS warning lamp driver cir-
cuit cavities of the cluster wire harness connector
within five seconds of turning the ignition switch to
the On position. If OK, replace the faulty bulb. If not
OK, go to Step 5.
(5) Disconnect and isolate the battery negative
cable. Unplug the Controller Anti-lock Brake (CAB)
wire harness connector. Check for continuity between
the ABS warning lamp driver circuit cavity of the
cluster wire harness connector and a good ground.
There should be no continuity. If OK, go to Step 6. If
not OK, repair the short circuit as required.
(6) Check for continuity between the ABS warning
lamp driver circuit cavities of the cluster wire har-
ness connector and the CAB wire harness connector.
There should be continuity. If OK, refer to Group 5 -
Brakes for diagnosis of the CAB. If not OK, repair
the open circuit as required.
ZG