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 power window and lock master switch unit from the driver side front door trim panel. Unplug the wire harness connector from the master switch unit.

(3) Check for continuity between the ground circuit cavity of the power window and lock master switch unit wire harness connector and a good ground. If ok, go to step 4. If not ok, repair the circuit to ground as required.

(4) Connect the battery negative cable. Turn the ignition switch to the on position. Check for battery voltage at the fused ignition switch output (run) circuit cavity of the power window and lock master switch unit wire harness connector. If ok, see power window switch in the diagnosis and testing section of this group. If not ok, repair the circuit to 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.

If the only inoperative window is in the driver side front door and the preceding checks have not identified a problem, see Power Window Motor in the Diagnosis and Testing section of this group. If the problem being diagnosed involves only the Auto-down feature for the driver side front door window, but all of the power windows are operational, replace the faulty power window and lock master switch unit. If the problem being diagnosed involves only an inoperative power window switch Light-Emitting Diode (LED), but the power window that the switch controls operates satisfactorily from that switch, replace the faulty switch unit. For any other single power window problem proceed with diagnosis as follows: (1) Disconnect and isolate the battery negative cable. Unplug the wire harness connector from the power window switch unit on the door with the inoperative power window. Check for continuity between the ground circuit cavity of the power window switch wire harness connector and a good ground. There should be continuity. If OK, go to Step 2. If not OK, repair the open circuit to the power window and door lock master switch as required.

(2) Connect the battery negative cable. Turn the ignition switch to the On position. Check for battery voltage at the fused ignition switch output (run) circuit cavity in the body half of the power window switch unit wire harness connector. If OK, go to Step 3. If not OK, repair the open circuit to the power window and door lock master switch as required.

(3) Test the power window switch continuity. See Power Window Switch in the Diagnosis and Testing section of this group. If OK, go to Step 4. If not OK, replace the faulty power window switch unit.

(4) Refer to the circuit diagrams in 8W-60 - Power Windows in Group 8W - Wiring Diagrams. Check the continuity in each circuit between the inoperative power window switch wire harness connector cavities and the corresponding power window motor wire harness connector cavities. If OK, see Power Window

Motor in the Diagnosis and Testing section of this group. If not OK, repair the open circuit(s) as required.

NOTE: All passenger door power window switches receive their battery and ground feed for operating the passenger door power window motors through the driver side power window and lock master switch and wire harness connector.

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.

Power window switch

The Light-Emitting Diode (LED) illumination lamps for all of the power window and lock switch and bezel unit switch paddles receive battery current through the power window circuit breaker in the junction block. If all of the LEDs are inoperative in both the power window and lock switch units and the power windows are inoperative, perform the diagnosis for Power Window System in this group. If the power windows operate, but any or all of the LEDs are inoperative, the power window and lock switch units with the inoperative LED(s) is faulty and must be replaced. For circuit descriptions and diagrams, refer to 8W-60 - Power Windows in Group 8W - Wiring Diagrams.

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

If OK, go to Step 2. If not OK, replace the faulty circuit breaker.

(2) Turn the ignition switch to the On position.

Check for battery voltage at the circuit breaker in the junction block. If OK, turn the ignition switch to the Off position and go to Step 3. If not OK, repair the circuit to the ignition switch as required.

(3) Disconnect and isolate the battery negative cable. Remove the power window switch unit from the door trim panel. Unplug the wire harness connector from the switch unit.

(4) Test the power window switch continuity. See the Power Window Switch Continuity charts to determine if the continuity is correct in the Off, Up and Down switch positions (Fig. 1) or (Fig. 2). If OK, see Power Window Motor in the Diagnosis and Testing section of this group. If not OK, replace the faulty switch.

Fig. 1 Power Window Switch Continuity - Driver Side Front

NOTE: Because this switch contains active electronic elements for the Auto-down feature, this switch function cannot be checked with a continuity test. If the problem being diagnosed involves this function, reconnect the switch to its wire harness connector, connect the battery negative cable and turn the ignition switch to the On position. Back probe the wire harness connector cavity for switch pin number 8 and check for the proper switch output while actuating the switch. With the switch in the Up position, there should be continuity to ground at pin 8. With the switch in the Down position, there should be battery voltage at pin 8.

Fig. 2 Power Window Switch Continuity - Passenger Doors

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 Power Window Switch in the Diagnosis and Testing section of 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 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.