Jeep 1997 Grand Cherokee Service Manual page 584

8S - 4 POWER WINDOW SYSTEMS
DIAGNOSIS AND TESTING (Continued)
senger side front or rear window that operates from
the switch on that door, but does not operate from
the master switch on the driver side front door, use a
DRB scan tool and the proper Body Diagnostic Pro-
cedures manual to diagnose the circuitry of the door
modules and the CCD data bus. For circuit descrip-
tions and diagrams, refer to 8W-60 - Power Windows
in Group 8W - Wiring Diagrams.
(1) Disconnect and isolate the battery negative
cable. Remove the front door trim panel as described
in this group. Go to Step 2.
(2) Check the 12-way door module wire harness
connector to see that it is fully seated in the door
module receptacle. If OK, go to Step 3. If not OK,
install the wire harness connector properly.
(3) Unplug the 12-way door module wire harness
connector from the door module. Check for continuity
between the ground circuit cavity of the door module
wire harness connector and a good ground. There
should be continuity. If OK, go to Step 4. If not OK,
repair the open circuit as required.
(4) Connect the battery negative cable. Check for
battery voltage at the fused B(+) circuit cavity of the
12-way door module wire harness connector. If OK,
go to Step 5. If not OK, repair the open circuit as
required.
(5) If the inoperative window is on a front door, go
to Step 6. If the inoperative window is on a rear door
go to Step 9.
(6) Disconnect and isolate the battery negative
cable. Unplug the inoperative power window motor
wire harness connector. Check for continuity between
the front window driver up circuit cavity of the
12-way door module wire harness connector and a
good ground. Repeat the check for the front window
driver down circuit cavity of the door module wire
harness connector. In each case there should be no
continuity. If OK, go to Step 7. If not OK, repair the
short circuit as required.
(7) Check for continuity between the front window
driver up circuit cavities of the 12-way door module
wire harness connector and the power window motor
wire harness connector. Repeat the check for the
front window driver down circuit cavities. In each
case there should be continuity. If OK, go to Step 8.
If not OK, repair the open circuit as required.
(8) Plug the 12-way door module wire harness con-
nector back into the door module. Connect the bat-
tery negative cable. Connect the probes of a
reversible DC digital voltmeter to the door module
side of the power window motor wire harness connec-
tor. Observe the voltmeter while actuating the switch
in the up and down directions. There should be bat-
tery voltage for as long as the switch is held in both
the up and down positions, and no voltage in the
neutral position. If OK, see the diagnosis for Power
Window Motors. If not OK, replace the faulty door
module.
(9) Disconnect and isolate the battery negative
cable. Remove the rear door power window switch as
described in this group. Check the rear door power
window switch continuity as described in this group.
If OK, go to Step 10. If not OK, replace the faulty
switch.
(10) Plug the rear door power window switch into
the wire harness connector. Unplug the inoperative
power window motor connector. Check for continuity
between the rear window driver up circuit cavity of
the 12-way door module wire harness connector and
a good ground. Repeat the check for the rear window
driver down circuit cavity. In each case there should
be no continuity. If OK, go to Step 11. If not OK,
repair the short circuit as required.
(11) Check for continuity between the rear window
driver up circuit cavities of the 12-way door module
wire harness connector and the power window motor
wire harness connector. Repeat the check for the rear
window driver down circuit cavities. In each case
there should be continuity. If OK, go to Step 12. If
not OK, repair the open circuit as required.
NOTE: The door module feeds battery voltage to
both terminals of the rear door power window
motors when the power window lockout switch is in
the Unlock position, until the master window switch
on the driver side front door is actuated. The door
module feeds ground to both terminals of the rear
door power window motor when the power window
lockout switch is in the Lock position, until the
master window switch on the driver side front door
is actuated.
(12) Plug the 12-way door module wire harness
connector back into the door module. Connect the
battery negative cable. Check for battery voltage at
each cavity of the switch side of the power window
motor wire harness connector. Each cavity should
have battery voltage in the neutral position. Each
cavity should also have battery voltage in one other
switch position, either up or down, and zero volts
with the switch in the opposite position. If OK, go to
the Power Window Motor diagnosis in this group. If
not OK, replace the faulty door module.
POWER WINDOW SWITCH
This diagnosis is for the rear door power window
switches. The front door power window switches are
integral to the door modules. For diagnosis of the
front door power window switches, see Door Module
in this group. For circuit descriptions and diagrams,
refer to 8W-60 - Power Windows in Group 8W - Wir-
ing Diagrams.
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