Hummer H3. Manual — part 1740

Circuit/System Description

The rear wiper motor module is part of the rear wiper motor assembly and controls wiper motor
operation. System voltage is supplied to the switch, washer pump and wiper motor by two
retained accessory power circuits. The washer switch controls the washer pump by providing a
path to ground when pressed. The rear washer control circuit is also used as a wash signal to the
rear wiper motor module. The WASH command on the washer control circuit will cause the
wiper motor to operate at low speed for as long as the switch is held in the closed position and 2
cycles after being released.

Reference Information

Schematic Reference

Wiper/Washer Schematics

Connector End View Reference

Wiper/Washer Connector End Views

Electrical Information Reference

Circuit Testing

Connector Repairs

Testing for Intermittent Conditions and Poor Connections

Wiring Repairs

Scan Tool Reference

Scan Tool Output Controls

Scan Tool Data List

Scan Tool Data Definitions

Circuit/System Testing

3. Wiper Motor Inoperative in One Delay Mode
4. Wiper Motor Always On
5. Washer Pump Inoperative
6. Washer Wipers Inoperative
7. Washer Wipers and Pump Inoperative
8. Washers Always On

2007 Hummer H3

2007 ACCESSORIES & EQUIPMENT Wipers and Washers - H3

Wiper Motor Inoperative in All Modes

1. Disconnect the rear wiper motor connector.

2. Ignition ON, verify that a test lamp will illuminate when connected from the wiper motor

supply circuit to ground.

If the test lamp does not illuminate repair the wiper motor supply circuit for an
open/high resistance or short to ground.

3. Verify that a test lamp will illuminate when connected from the wiper motor ground circuit

to battery voltage.

If the test lamp does not illuminate repair the wiper motor ground circuit for an
open/high resistance.

4. If all the circuits test normal replace the rear wiper motor.

Wiper Motor Inoperative in Both Delay Modes

1. Verify that the wiper fuse is not open.

If the wiper fuse is open repair the short to ground in the switch supply, delay 1 signal,
delay 2 signal or washer pump control circuit.

2. Disconnect the wiper switch connector.

3. Ignition ON, verify that a test lamp will illuminate when connected between the wiper

switch supply circuit and ground.

If the test lamp does not illuminate repair the wiper switch supply circuit for an
open/high resistance.

4. Connect the wiper switch connector.

5. Disconnect the wiper motor connector.

6. Connect a test lamp between the delay 1 signal circuit and ground.

7. Turn the rear wiper switch to the delay 1 position, the test lamp should illuminate.

If the test lamp does not illuminate replace the rear wiper/washer switch.

8. If all the circuits test normal replace the rear wiper motor.

Wiper Motor Inoperative in One Delay Mode

1. Disconnect the rear wiper motor connector.

2. Connect a test lamp between the inoperative delay signal circuit and ground.

3. Ignition ON, turn the rear wiper switch to the inoperative delay position, the test lamp

should illuminate.

2007 Hummer H3

2007 ACCESSORIES & EQUIPMENT Wipers and Washers - H3

If the test lamp does not illuminate test the inoperative delay signal circuit for an
open/high resistance. If the circuit tests normal replace the rear wiper switch.

4. If all the circuits test normal replace the rear wiper motor.

Wiper Motor Always On

1. Disconnect the rear wiper motor connector.

2. Connect a test lamp between the delay 1 signal circuit and ground.

3. Ignition ON, wiper switch OFF, the test lamp should not illuminate.

If the test lamp illuminates test the delay 1 signal circuit for a short to voltage. If the
circuit tests normal replace the rear wiper switch.

4. Connect a test lamp between the delay 2 signal circuit and ground.

5. Ignition ON, wiper switch OFF, the test lamp should not illuminate.

If the test lamp illuminates test the delay 2 signal circuit for a short to voltage. If the
circuit tests normal replace the rear wiper switch.

6. If all the circuits test normal replace the rear wiper motor.

Washer Pump Inoperative

1. Disconnect the rear washer pump connector.

2. Connect a test lamp between the washer pump supply circuit and ground.

3. Ignition ON, the test lamp should illuminate.

If the test lamp does not illuminate repair the rear washer pump supply circuit for an
open/high resistance.

4. Connect a test lamp between the washer pump supply circuit and control circuit.

5. Ignition ON, washer switch pressed, the test lamp should illuminate.

If the test lamp does not illuminate test the washer pump control and switch ground
circuits for an open/high resistance. If the circuits test normal replace the rear wiper
washer switch.

6. If all the circuits test normal replace the rear washer pump.

Washer Wiper Inoperative

1. Disconnect the rear wiper motor connector.

2. Connect a test lamp between battery voltage and the washer pump control circuit.

3. The test lamp should illuminate while the washer switch is pressed.

2007 Hummer H3

2007 ACCESSORIES & EQUIPMENT Wipers and Washers - H3

If the test lamp does not illuminate repair the washer pump control circuit for an
open/high resistance.

4. If all the circuits test normal replace the rear wiper motor.

Washer Wipers and Pump Inoperative

1. Disconnect the rear washer pump connector.

2. Connect a test lamp between battery voltage and the washer pump control circuit.

3. The test lamp should illuminate while the washer switch is pressed.

If the test lamp does not illuminate test the washer pump control and switch ground
circuits for an open/high resistance. If the circuits test normal replace the rear wiper
washer switch.

Washers Always On

1. Disconnect the rear wiper motor connector.

2. Connect a test lamp between battery voltage and the washer pump control circuit.

3. The test lamp should not illuminate while the washer switch is OFF.

If the test lamp illuminates repair the washer pump control circuit for a short to
ground. If the circuit tests normal replace the rear wiper washer switch.

4. If all the circuits test normal replace the rear wiper motor.

Repair Procedures

Rear Window Washer Pump Replacement

Rear Window Wiper Motor Replacement

Rear Window Wiper and Washer Switch Replacement

WIPER ARM TIP PRESSURE CHECK

IMPORTANT: Always perform the Diagnostic Repair Verification after

completing the diagnostic procedure.

2007 Hummer H3

2007 ACCESSORIES & EQUIPMENT Wipers and Washers - H3