Jeep Grand Cherokee WJ. Manual - part 159
POWER LUMBAR SWITCH
For complete circuit diagrams, refer to Power
Seat in the Contents of Group 8W - Wiring Dia-
grams.
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the power lumbar switch from the out-
board seat cushion side shield. Refer to Power Lum-
bar Switch in the Removal and Installation section
of this group for the procedures.
(3) Use an ohmmeter to test the continuity of the
power lumbar switch in each switch position. See the
Power Lumbar Switch Continuity chart (Fig. 6). If
OK, refer to Power Lumbar Adjuster in the Diag-
nosis and Testing section of this group. If not OK,
replace the faulty power lumbar switch.
POWER SEAT RECLINER
Following are tests that will help to diagnose the
hard wired components and circuits of the power seat
system. However, if the vehicle is also equipped with
the optional memory system, these tests may not
prove conclusive in the diagnosis of the driver side
power seat. In order to obtain conclusive testing of
the driver side power seat with the memory system
option, the Programmable Communications Interface
(PCI) data bus network and all of the electronic mod-
ules that provide inputs to, or receive outputs from
the memory system components must be checked.
The most reliable, efficient, and accurate means to
diagnose the driver side power seat with the memory
system option requires the use of a DRB scan tool
and the proper Diagnostic Procedures manual. The
DRB scan tool can provide confirmation that the PCI
data bus is functional, that all of the electronic mod-
ules are sending and receiving the proper messages
on the PCI data bus, and that the memory system is
receiving the proper hard wired inputs and relaying
the proper hard wired outputs to perform its driver
side power seat functions.
Actuate the power seat recliner switch to move the
power seat recliner adjuster in each direction. The
power seat recliner adjuster should move in both
directions. If the power seat recliner adjuster fails to
operate in only one direction, move the adjuster a
short distance in the opposite direction and test
again to be certain that the adjuster is not at its
travel limit. If the power seat recliner adjuster still
fails to operate in only one direction, refer to Power
Seat Switch in the Diagnosis and Testing section of
this group. If the power recliner adjuster fails to
operate in either direction, perform the following
tests. For complete circuit diagrams, refer to Power
Seat in the Contents of Group 8W - Wiring Dia-
grams.
(1) Check the power seat circuit breaker in the
junction block. If OK, go to Step 2. If not OK, replace
the faulty power seat circuit breaker.
(2) Check for battery voltage at the power seat cir-
cuit breaker in the junction block. If OK, go to Step
3. If not OK, repair the open fused B(+) circuit to the
fuse in the Power Distribution Center as required.
(3) Remove the outboard seat cushion side shield
from the seat. Disconnect the seat wire harness con-
nector from the power seat switch connector recepta-
cle. Check for battery voltage at the fused B(+)
circuit cavity of the power seat wire harness connec-
tor for the power seat switch. If OK, go to Step 4. If
not OK, repair the open fused B(+) circuit to the
power seat circuit breaker in the junction block as
required.
(4) Check for continuity between the ground cir-
cuit cavity of the power seat wire harness connector
for the power seat switch and a good ground. There
should be continuity. If OK, go to Step 5. If not OK,
repair the open ground circuit to ground as required.
(5) Test the power seat switch. Refer to Power
Seat Switch in the Diagnosis and Testing section of
this group. If the switch tests OK, test the circuits of
the power seat wire harness between the power seat
recliner adjuster motor and the power seat switch for
Fig. 6 Power Lumbar Switch Continuity
POWER LUMBAR SWITCH
LEFT SWITCH
POSITION
RIGHT
SWITCH
POSITION
CONTINUITY
BETWEEN
Off
Off
2-4, 3-5
Forward
Rearward
3-5, 4-6
Rearward
Forward
2-4, 3-6
8R - 6
POWER SEAT SYSTEMS
WJ
DIAGNOSIS AND TESTING (Continued)