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 ohms 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 delay 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

Did you perform the Diagnostic System Check - Vehicle?

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Go to Step 2

Go to Diagnostic System Check - Vehicle

2

  1. Turn the ignition ON.
  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

Do the windshield wipers 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 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 lamp 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 lamp illuminate?

--

Go to Step 6

Go to Step 10

6

  1. Connect the test lamp from the wiper switch signal 1 circuit of the module connector to a good ground.
  2. Place the windshield wiper/washer switch in the following positions:
  3. • MIST
    • LO
    • HI

Does the test lamp illuminate in each of the listed switch 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
    • INT
    • LO
    • HI

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

24K ohms

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 measure within the specified values in each of the wiper switch delay positions?

38K-690K ohms

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 .

Did 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 .

Did 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 .

Did you find and correct the condition?

--

Go to Step 16

Go to Step 12

12

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 16

Go to Step 14

13

Inspect 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 .

Did 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 .

Did you complete the replacement?

--

Go to Step 16

--

15

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

Did you complete the replacement?

--

Go to Step 16

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16

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 2