Jeep XJ Manual - page 5
DIAGNOSIS AND TESTING
INSTRUMENT CLUSTER
If all of the gauges and/or indicator lamps are inop-
erative, perform the Preliminary Diagnosis. If an
individual gauge or Chrysler Collision Detection
(CCD) data bus message-controlled indicator lamp is
inoperative, go directly to the Actuator Test. If an
individual hard wired indicator lamp is inoperative,
refer to Instrument Cluster - Hard Wired Lamp
Diagnosis in the Diagnosis and Testing section of
this group for the procedures to diagnosis that lamp.
For complete circuit diagrams, refer to Instrument
Cluster in the Contents of Group 8W - Wiring Dia-
grams.
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS,
REFER
TO
GROUP
8M
-
PASSIVE
RESTRAINT SYSTEMS BEFORE ATTEMPTING ANY
STEERING
WHEEL,
STEERING
COLUMN,
OR
INSTRUMENT PANEL COMPONENT DIAGNOSIS OR
SERVICE. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
PRELIMINARY DIAGNOSIS
(1) If the indicator lamps operate, but none of the
gauges operate, go to Step 2. If all of the gauges and
the data bus message-controlled indicator lamps are
inoperative, go to Step 5.
(2) Check the fused B(+) fuse in the Power Distri-
bution Center (PDC). If OK, go to Step 3. If not OK,
repair the shorted circuit or component as required
and replace the faulty fuse.
(3) Check for battery voltage at the fused B(+) fuse
in the PDC. If OK, go to Step 4. If not OK, repair the
open fused B(+) circuit to the battery as required.
(4) Disconnect and isolate the battery negative
cable. Remove the instrument cluster. Connect the
battery negative cable. Check for battery voltage at
the fused B(+) circuit cavity of the instrument cluster
wire harness connector A. If OK, refer to Instru-
ment Cluster - Actuator Test in the Diagnosis and
Testing section of this group. If not OK, repair the
open fused B(+) circuit to the fuse in the PDC as
required.
(5) Check the fused ignition switch output (run/
start) fuse in the junction block. If OK, go to Step 6.
If not OK, repair the shorted circuit or component as
required and replace the faulty fuse.
(6) Turn the ignition switch to the On position and
check for battery voltage at the fused ignition switch
output (run/start) fuse in the junction block. If OK,
go to Step 7. If not OK, repair the open fused ignition
switch output (run/start) circuit to the ignition switch
as required.
(7) Turn the ignition switch to the Off position.
Disconnect and isolate the battery negative cable.
Install the instrument cluster. Connect the battery
negative cable. Turn the ignition switch to the On
position. Set the park brake. The red brake warning
lamp should light. If OK, go to Step 8. If not OK, go
to Step 9.
(8) Turn the ignition switch to the Off position.
Turn on the park lamps and adjust the panel lamps
dimmer rheostat in the headlamp switch to the full
bright
position.
The
cluster
illumination
lamps
should light. If OK, refer to Instrument Cluster -
Actuator Test in the Diagnosis and Testing section
of this group. If not OK, go to Step 10.
(9) Turn the ignition switch to the Off position.
Disconnect and isolate the battery negative cable.
Remove the instrument cluster. Connect the battery
negative cable. Turn the ignition switch to the On
position. Check for battery voltage at the fused igni-
tion switch output (run/start) circuit cavity of the
instrument cluster wire harness connector A. If OK,
refer to Instrument Cluster - Actuator Test in the
Diagnosis and Testing section of this group. If not
OK, repair the open fused ignition switch output
(run/start) circuit to the fuse in the junction block as
required.
(10) Disconnect and isolate the battery negative
cable. Remove the instrument cluster. Check for con-
tinuity between the ground circuit cavity of the
instrument cluster wire harness connector A and a
good ground. There should be continuity. If OK, refer
to Instrument Cluster - Actuator Test in the
Diagnosis and Testing section of this group. If not
OK, repair the open ground circuit to ground as
required.
ACTUATOR TEST
The instrument cluster actuator test will put the
instrument cluster into its self-diagnostic mode. In
this mode the instrument cluster can perform a self-
diagnostic test that will confirm that the instrument
cluster circuitry, the gauges, and the CCD data bus
message controlled indicator lamps are capable of
operating as designed. During the actuator test the
instrument cluster circuitry will position each of the
gauge needles at various specified calibration points,
and turn all of the CCD data bus message-controlled
lamps on and off at specified time intervals (Fig. 1)
or (Fig. 2).
Successful completion of the actuator test will con-
firm that the instrument cluster is operational. How-
ever, there may still be a problem with the CCD data
bus, the Powertrain Control Module (PCM), the Air-
bag Control Module (ACM), the Sentry Key Immobi-
XJ
INSTRUMENT PANEL SYSTEMS
8E - 5