GM Service Manual Online
For 1990-2009 cars only

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. This step verifies the high-speed operation of the wiper motor. With the wiper switch in the high-speed position, and with an open in the wiper motor high speed signal circuit, the wiper motor will operate in the low-speed mode.

  2. This step tests for continuity through the 24K ohm resistor in the windshield wiper/washer switch. The connector behind the instrument panel knee bolster is suitable for performing this step.

  3. This step tests for continuity through the delaym resistors in the windshield wiper/washer switch. The measured resistance will change in sequence from high to low as the delay speed is increased. The connector behind the instrument panel knee bolster is suitable for performing this step.

Step

Action

Values

Yes

No

Schematic Reference: Wiper/Washer Schematics .

Connector End View Reference: Wiper/Washer Connector End Views .

1

Have you conducted Diagnostic System Check - Vehicle?

--

Go to Step 2

Go to the Diagnostic System Check - Vehicle

2

  1. Turn ON the ignition.
  2. Operate the windshield wiper/washer switch through all the switch positions.

Does the windshield wiper/washer system operate normally?

--

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

3

Does the windshield wiper operate at high speed with the switch in the high speed mode?

--

Go to Step 5

Go to Step 4

4

  1. Turn OFF the ignition.
  2. Disconnect the windshield wiper/washer module connector.
  3. Connect a test lamp from the windshield wiper motor high speed signal circuit of the wiper/washer module connector to a good ground.
  4. Turn ON the ignition.
  5. Place the windshield wiper/washer switch in the high speed position.

Does the test light illuminate?

--

Go to Step 13

Go to Step 9

5

  1. Turn OFF the ignition.
  2. Disconnect the windshield wiper/washer module connector.
  3. Connect a test lamp from the wiper switch signal 2 circuit of the module connector to a good ground.
  4. Turn ON the ignition.
  5. Press the windshield washer switch.

Does the test light illuminate?

--

Go to Step 6

Go to Step 10

6

  1. Connect a test lamp from the windshield wiper switch signal 1 circuit of the wiper/washer module connector to a good ground.
  2. Place the windshield wiper/washer switch in the following positions.
  3. • MIST (DEFOG)
    • LO (Low speed)
    • High

Does the test light ever illuminate in one of positions?

--

Go to Step 7

Go to Step 11

7

  1. Disconnect the windshield wiper/washer switch connector.
  2. Measure the resistance between the windshield wiper/ washer switch signal 2 terminal of the switch and the battery positive voltage terminal of the switch.
  3. Place the windshield wiper/washer switch in the following positions.
  4. • MIST (DEFOG)
    • INT (Intermittent)
    • LO (Low speed)
    • High

Does the resistance measure at or near the specified value in all the listed switch positions?

24 ohm

Go to Step 8

Go to Step 12

8

  1. Measure the resistance between the windshield wiper/ washer switch signal 1 terminal of the switch and the battery positive voltage terminal of the switch.
  2. Place the windshield wiper/washer switch in each of the delay positions.

Does the resistance measured within the specified values in each of the wiper switch delay positions?

38 K ohm to 690 K ohm

Go to Step 13

Go to Step 12

9

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

Do you find and correct the condition?

--

Go to Step 16

Go to Step 12

10

Test the windshield wiper switch signal 2 circuit for a short to ground or an open. Refer to Circuit Testing and Wiring Repairs .

Do you find and correct the condition?

--

Go to Step 16

Go to Step 12

11

Test the windshield wiper switch signal 1 circuit for a short to ground or an open. Refer to Circuit Testing and Wiring Repairs .

Do you find and correct the condition?

--

Go to Step 16

Go to Step 12

12

Check 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 .

Do you find and correct the condition?

--

Go to Step 16

Go to Step 14

13

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

Do you find and correct the condition?

--

Go to Step 16

Go to Step 15

14

Replace the windshield wiper/washer switch. Refer to Turn Signal Multifunction Switch Replacement .

Have you finished the replacement?

--

Go to Step 16

--

15

Replace the windshield wiper/washer module. Refer to Windshield Wiper System Module Replacement .

Have you finished the replacement?

--

Go to Step 16

--

16

Operate the system to verify the repair.

Is the failure removed?

--

System OK

Go to Step 2