Jeep Cherokee (XJ): Diagnosis and testing

Power window system

For circuit descriptions and diagrams, refer to 8W-60 - Power Windows in Group 8W - Wiring Diagrams.

ALL WINDOWS INOPERATIVE

(1) Check the circuit breaker in the junction block, as described in this group. If OK, go to Step 2. If not OK, replace the faulty circuit breaker.

(2) Disconnect and isolate the battery negative cable. Remove the driver side front door trim panel and unplug the Driver Door Module (DDM) wire harness connectors from the DDM. Check for continuity between the ground circuit cavity of the 8-way DDM wire harness connector and a good ground. If OK, go to Step 3. If not OK, repair the circuit to ground as required.

(3) Connect the battery negative cable. Turn the ignition switch to the On position. Check for battery voltage at the master switch power feed (run/acc) circuit cavity of the 12-way DDM wire harness connector.

If OK, see the diagnosis for the Door Module in this group. If not OK, repair the open circuit to the circuit breaker in the junction block as required.

ONE WINDOW INOPERATIVE

The window glass must be free to slide up and down for the power window motor to function properly.

If the glass is not free to move up and down, the motor will overload and trip the integral circuit breaker. To determine if the glass is free, disconnect the regulator plate from the glass. Then slide the window up and down by hand.

There is an alternate method to check if the glass is free. Position the glass between the up and down stops. Then, shake the glass in the door. Check that the glass can be moved slightly from side to side, front to rear, and up and down. Then check that the glass is not bound tight in the tracks. If the glass is free, proceed with the diagnosis that follows. If the glass is not free, refer to Group 23 - Body for the door window glass and hardware service and adjustment procedures.

(1) Check the power window switch continuity as described in the diagnosis for the Door Module (front doors) or Power Window Switch (rear doors) in this group. If OK and the driver side front window is inoperative, see the Power Window Motor diagnosis in this group. If OK and the inoperative window is other than the driver side front, go to Step 2. If not OK, replace the faulty door module or switch.

(2) Refer to the circuit diagrams in 8W-60 - Power Windows in Group 8W - Wiring Diagrams. Check the continuity in each circuit between the inoperative Passenger Door Module (PDM) or power window switch wire harness connector cavities and the corresponding Driver Door Module (DDM) wire harness connector cavities. If OK, see the diagnosis for the Power Window Motor in this group. If not OK, repair the open circuit(s) as required.

NOTE: All individual power window switches receive their battery and ground feeds through the Driver Door Module (DDM) and wire harness connectors.

Circuit breaker

For circuit descriptions and diagrams, refer to 8W-60 - Power Windows in Group 8W - Wiring Diagrams.

(1) Locate the circuit breaker in the junction block.

Pull out the circuit breaker slightly, but be certain that the circuit breaker terminals still contact the terminals in the junction block cavities.

(2) Connect the negative lead of a 12-volt DC voltmeter to a good ground.

(3) With the voltmeter positive lead, check both terminals of the circuit breaker for battery voltage.

If only one terminal has battery voltage, the circuit breaker is faulty and must be replaced. If neither terminal has battery voltage, repair the open circuit from the Power Distribution Center (PDC) as required. If the circuit breaker checks OK, but no power windows operate, see Power Window System in the Diagnosis and Testing section of this group.

Door module

The Driver Door Module (DDM) contains the master switches and the lockout switch in the power window system. The DDM also contains an integrated circuit to support the one-touch down feature of the driver side front door power window. Remember that the passenger side front door power window switch and, on four-door models, the rear door power window switches get their battery current through the power window lockout switch in the Driver Door Module (DDM). In addition, each individual power window switch gets its ground through the master switch in the DDM.

The one-touch down feature circuitry within the DDM will not operate the power window motor if the door glass, window regulator, or gearbox mechanism are stuck, obstructed, or binding. If the driver side front door power window operates as designed, but the one-touch down feature is inoperative, replace the faulty DDM.

If the problem being diagnosed is an inoperative power window switch illumination lamp, but the power window switch operates as designed, replace the faulty door module. For circuit descriptions 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 and unplug the door module wire harness connectors from the door module.

(2) Check the door module power window switch and/or power window lockout switch continuity in each position, as shown in the proper chart (Fig. 1) or (Fig. 2). If OK, see the Power Window Motor diagnosis in this group. If not OK, replace the faulty door module.

Fig. 1 DDM Power Window Switch Continuity

Fig. 2 PDM Power Window Switch Continuity

Power window switch

The diagnosis found here applies only to the rear door power window switches. For diagnosis of the front door power window switches, see Door Module in this group. If the problem being diagnosed is an inoperative power window switch illumination lamp, but the power window switch operates as designed, replace the faulty switch. For circuit descriptions and diagrams, refer to 8W-60 - Power Windows in Group 8W - Wiring Diagrams.

(1) Disconnect and isolate the battery negative cable.

(2) Remove the power window switch from the rear door trim panel.

(3) Check the power window switch continuity in each position as shown in the Rear Door Power Window Switch Continuity chart (Fig. 3). If OK, see the Power Window Motor diagnosis in this group. If not OK, replace the faulty switch.

Fig. 3 Rear Door Power Window Switch Continuity

Power window motor

For circuit descriptions and diagrams, refer to 8W-60 - Power Windows in Group 8W - Wiring Diagrams.

Before you proceed with this diagnosis, confirm proper switch operation. See the Door Module and/or Power Window Switch diagnosis in this group.

(1) Disconnect and isolate the battery negative cable. Remove the trim panel from the door with the inoperative power window.

(2) Unplug the power window motor wire harness connector. Apply 12 volts across the motor terminals to check its operation in one direction. Reverse the connections across the motor terminals to check the operation in the other direction. Remember, if the window is in the full up or full down position, the motor will not operate in that direction by design. If OK, repair the circuits from the power window motor to the door module or the power window switch as required. If not OK, replace the faulty motor.

(3) If the motor operates in both directions, check the operation of the window glass and lift mechanism through its complete up and down travel. There should be no binding or sticking of the window glass or lift mechanism through the entire travel range. If not OK, refer to Group 23 - Body to check the window glass, tracks, and regulator for sticking, binding, or improper adjustment.