GM Service Manual Online
For 1990-2009 cars only

Washers Inoperative Without Rear Wiper

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

  1. Turn ON the ignition.
  2. Press the windshield washer switch.

Does the windshield washer pump operate?

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

3

  1. Observe the Wash Switch parameter with a scan tool.
  2. Press the windshield washer switch.

Does the scan tool indicate the wash switch is ON?

Go to Step 4

Go to Step 5

4

  1. Disconnect the windshield washer pump connector.
  2. Probe the windshield washer pump control circuit with a test lamp connected to a good ground.
  3. Press the windshield washer switch.

Does the test lamp illuminate?

Go to Step 6

Go to Step 7

5

  1. Disconnect the harness connector from the body control module (BCM) that contains windshield washer switch signal from the switch.
  2. Probe the windshield washer switch signal circuit with a test lamp connected to a good ground.
  3. Press the windshield washer switch.

Does the test lamp illuminate?

Go to Step 12

Go to Step 8

6

Test the windshield washer pump ground circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 16

Go to Step 10

7

  1. Disconnect the BCM harness connector containing the windshield washer pump control circuit.
  2. Test the windshield washer pump control circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 16

Go to Step 12

8

  1. Disconnect the windshield washer switch.
  2. Test the windshield washer switch voltage supply circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 16

Go to Step 9

9

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

Did you find and correct the condition?

Go to Step 16

Go to Step 11

10

Inspect for poor connections at the windshield washer pump. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 16

Go to Step 13

11

Inspect for poor connections at 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 16

Go to Step 14

12

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

Did you find and correct the condition?

Go to Step 16

Go to Step 15

13

Replace the windshield washer pump. Refer to Washer Pump Replacement .

Did you complete the replacement?

Go to Step 16

--

14

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

Did you complete the replacement?

Go to Step 16

--

15

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

Did you complete the replacement?

Go to Step 16

--

16

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3

Washers Inoperative With Rear Wiper

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

Operate the front and rear windshield washers.

Do both washers operate properly?

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

3

Are only the front windshield washers inoperative?

Go to Step 9

Go to Step 4

4

Are only the rear windshield washers inoperative?

Go to Step 7

Go to Step 5

5

  1. Disconnect the front/rear window washer fluid pump.
  2. Probe the front windshield washer pump supply voltage circuit with a test lamp that is connected to a good ground.
  3. Operate the front windshield washers.

Does the test lamp illuminate?

Go to Step 6

Go to Step 21

6

  1. Probe the rear washer fluid pump supply voltage circuit with a test lamp that is connected to a good ground.
  2. Operate the rear windshield washers.

Does the test lamp illuminate?

Go to Step 16

Go to Step 22

7

  1. Disconnect the rear wiper/washer switch.
  2. Turn ON the ignition.
  3. Probe the ignition voltage circuit with a test lamp that is connected to a good ground.

Does the test lamp illuminate?

Go to Step 8

Go to Step 24

8

Connect a fused jumper wire between the ignition positive voltage circuit and the rear wiper switch delay/on signal circuit.

Do the rear wipers operate?

Go to Step 20

Go to Step 14

9

  1. Observe the Wash Switch parameter with a scan tool.
  2. Press the windshield washer switch.

Does the scan tool indicate the wash switch is ON?

Go to Step 10

Go to Step 11

10

  1. Disconnect the rear window wiper module.
  2. Probe the windshield washer pump control circuit with a test lamp connected to a good ground.
  3. Press the windshield washer switch.

Does the test lamp illuminate?

Go to Step 19

Go to Step 15

11

  1. Disconnect the harness connector from the body control module (BCM) that contains windshield washer switch signal from the switch.
  2. Probe the windshield washer switch signal circuit with a test lamp connected to a good ground.
  3. Press the windshield washer switch.

Does the test lamp illuminate?

Go to Step 18

Go to Step 12

12

  1. Disconnect the windshield washer switch.
  2. Test the windshield washer switch voltage supply circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 30

Go to Step 13

13

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

Did you find and correct the condition?

Go to Step 30

Go to Step 17

14

Test the rear wiper switch delay/on signal circuit for an open or short to ground. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 30

Go to Step 19

15

Test the windshield washer pump control circuit for an open or short to ground. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 30

Go to Step 18

16

Inspect for poor connections at the front/rear window washer fluid pump. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 30

Go to Step 25

17

Inspect for poor connections at 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 30

Go to Step 26

18

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

Did you find and correct the condition?

Go to Step 30

Go to Step 27

19

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

Did you find and correct the condition?

Go to Step 30

Go to Step 28

20

Inspect for poor connections at the rear 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 30

Go to Step 29

21

Repair an open or high resistance in the front windshield washer pump supply voltage circuit. Refer to Circuit Testing and Wiring Repairs .

Did you correct the condition?

Go to Step 30

--

22

Repair an open or high resistance in the rear washer fluid pump supply voltage circuit. Refer to Circuit Testing and Wiring Repairs .

Did you correct the condition?

Go to Step 30

--

23

Repair an open or high resistance in the windshield washer pump control circuit. Refer to Circuit Testing and Wiring Repairs .

Did you correct the condition?

Go to Step 30

--

24

Repair an open, high resistance, or short to ground in the ignition positive voltage circuit. Refer to Circuit Testing and Wiring Repairs .

Did you correct the condition?

Go to Step 30

--

25

Replace the front/rear window washer pump. Refer to Washer Pump Replacement

Go to Step 30

--

26

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

Did you complete the replacement?

Go to Step 30

--

27

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

Did you complete the replacement?

Go to Step 30

--

28

Replace the rear window wiper module. Refer to Liftgate Wiper Motor Replacement

Go to Step 30

--

29

Replace the rear wiper/washer switch. Refer to Console Replacement

Go to Step 30

--

30 

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3