GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Wiper/Washer Schematics

Connector End View Reference: Wiper/Washer Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

Do the wipers operate for approximately 7 seconds in the low or delay modes then stop.

Go to Step 10

Go to Step 3

3

Place the wiper switch in the LOW speed position.

Do the windshield wipers operate?

Go to Step 4

Go to Step 9

4

With the wiper switch in the LOW speed position, do the wipers operate at HIGH speed?

Go to Step 19

Go to Step 5

5

Place the wiper switch in the HIGH speed position.

Do the windshield wipers operate at high speed?

Go to Step 6

Go to Step 14

6

  1. The wipers do not return to the PARK position when the wiper switch is turned OFF.
  2. The windshield wipers display erratic operation in the DELAY modes.

Do the windshield wipers display either one of the above symptoms?

Go to Step 10

Go to Step 7

7

Turn the wiper switch through each DELAY position.

Do the windshield wipers operate in each delay position?

Go to Step 8

Go to Step 24

8

Place the wiper switch in the MIST position.

Do the windshield wipers operate at low speed?

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 28

9

  1. Install a scan tool.
  2. Place the wiper switch in the LOW speed position.
  3. With a scan tool, observe the Windshield Wiper Switch parameter in the Body Control Module data list.

Does the Windshield Wiper Switch parameter display Low/Mist/High?

Go to Step 12

Go to Step 18

10

  1. Turn OFF the ignition.
  2. Install a scan tool.
  3. Disconnect the windshield wiper motor.
  4. Connect a 3-amp fused jumper wire from the windshield wiper motor park switch signal circuit of the wiper motor connector to a good ground.
  5. Turn ON the ignition, with the engine OFF.
  6. With a scan tool, observe the Windshield Wiper Park Switch parameter in the Body Control Module data list.

Does the Windshield Wiper Park Switch parameter display ON?

Go to Step 11

Go to Step 23

11

Connect a test lamp from the accessory voltage circuit of the wiper motor connector to a good ground.

Does the test lamp illuminate?

Go to Step 27

Go to Step 30

12

  1. Remove the wiper ON/OFF relay from the underhood fuse block. Refer to Relay Replacement .
  2. Place the wiper switch in the LOW speed position.
  3. Probe the windshield wiper switch signal 2 circuit of the ON/OFF relay with a test lamp that is connected to a good ground.

Does the test lamp illuminate?

Go to Step 13

Go to Step 29

13

  1. Turn OFF the ignition.
  2. Install the wiper ON/OFF relay.
  3. Disconnect the windshield wiper motor.
  4. Turn ON the ignition, with the engine OFF.
  5. Place the wiper switch in the LOW speed position.
  6. Connect a test lamp from the windshield wiper motor low speed control circuit of the wiper motor connector to a good ground.

Does the test lamp illuminate?

Go to Step 27

Go to Step 20

14

  1. Remove the wiper HI/LO relay from the underhood fuse block. Refer to Relay Replacement .
  2. Place the wiper switch in the HIGH speed position.
  3. Probe the windshield wiper switch high signal circuit of the HI/LO relay with a test lamp connected to a good ground.

Does the test lamp illuminate?

Go to Step 15

Go to Step 22

15

Connect the test lamp between the windshield wiper switch high speed signal circuit of the wiper HI/LO relay and the coil ground circuit of the wiper HI/LO relay.

Does the test lamp illuminate?

Go to Step 16

Go to Step 31

16

  1. Turn OFF the ignition.
  2. Remove the wiper ON/OFF relay from the underhood fuse block. Refer to Relay Replacement .
  3. Turn ON the ignition, with the engine OFF.
  4. Place the wiper switch in the HIGH speed position.
  5. Probe the windshield wiper switch signal 2 circuit of the wiper ON/OFF relay with a test lamp that is connected to a good ground.

Does the test lamp illuminate?

Go to Step 17

Go to Step 26

17

  1. Turn OFF the ignition.
  2. Disconnect the windshield wiper motor.
  3. Install the wiper HI/LO and ON/OFF relays.
  4. Turn ON the ignition, with the engine OFF.
  5. Place the wiper switch in the HIGH speed position.
  6. Probe the wiper high speed control circuit of the wiper motor connector with a test lamp connected to a good ground.

Does the test lamp illuminate?

Go to Step 27

Go to Step 20

18

  1. Turn OFF the ignition.
  2. Disconnect the wiper switch.
  3. Turn ON the ignition, with the engine OFF.
  4. Connect a 3-amp fused jumper wire between the battery positive voltage circuit of the wiper switch connector and the windshield wiper switch low signal circuit of the wiper switch connector.
  5. With a scan tool, observe the Windshield Wiper Switch parameter.

Does the Windshield Wiper Switch parameter display Low?

Go to Step 28

Go to Step 21

19

  1. Place the wiper switch in the OFF position.
  2. Remove the wiper diode from the underhood fuse block.
  3. Place the wiper switch in the LOW speed position.

Do the wipers operate at low speed?

Go to Step 26

Go to Step 25

20

Test the appropriate high or low speed control circuit of the windshield wiper motor for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 37

Go to Step 25

21

Test the windshield wiper switch low signal circuit between the switch and the BCM for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 37

Go to Step 29

22

Test the windshield wiper switch high signal circuit between the wiper switch and the wiper HI/LO relay for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 37

Go to Step 28

23

Test the windshield wiper motor park switch signal circuit for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 37

Go to Step 29

24

Test the windshield wiper motor park switch signal circuit between the ON/OFF relay and the WIPER DWELL fuse for a high resistance or an open. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 37

Go to Step 28

25

Inspect for poor connections at the wiper HI/LO relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 37

Go to Step 32

26

Inspect for poor connections at the wiper diode. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 37

Go to Step 33

27

Inspect for poor connections at the harness connector of the windshield wiper motor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 37

Go to Step 34

28

Inspect for poor connections at the harness connector of the windshield wiper/washer switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 37

Go to Step 35

29

Inspect for poor connections at the harness connector of the BCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 37

Go to Step 36

30

Repair the open in the accessory voltage circuit of the windshield wiper motor. Refer to Wiring Repairs .

Did you complete the repair?

Go to Step 37

--

31

Repair the high resistance or open in the ground circuit of the relay. Refer to Wiring Repairs .

Did you complete the repair?

Go to Step 37

--

32

Replace the windshield wiper HI/LO relay. Refer to Relay Replacement .

Did you complete the replacement?

Go to Step 37

--

33

Replace the windshield wiper diode.

Did you complete the replacement?

Go to Step 37

--

34

Replace the windshield wiper motor. Refer to Windshield Wiper Motor Replacement .

Did you complete the replacement?

Go to Step 37

--

35

Replace the windshield wiper/washer switch. Refer to Windshield Wiper and Washer Switch Replacement .

Did you complete the replacement?

Go to Step 37

--

36

Replace the BCM. Refer to Control Module References for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 37

--

37

  1. Reconnect all previous disconnected components.
  2. Clear all DTCs with a scan tool.
  3. Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2