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 tests for continuity through the 680 ohms resistor in the windshield wiper/washer switch. The connector behind the instrument panel knee bolster is suitable for performing this step.

  2. 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

Value(s)

Yes

No

Schematic Reference: Wiper/Washer Schematics

1

Did you review the Wiper/Washer System Description and Operation and perform the necessary inspections?

--

Go to Step 2

Go to Symptoms - Wiper/Washer Systems

2

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

Does the windshield wiper/washer system operate normally?

--

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 3

3

Do the windshield wipers operate in the high speed mode?

--

Go to Step 5

Go to Step 4

4

  1. Disconnect the windshield wiper motor connector.
  2. Connect a test lamp from the windshield wiper motor high speed circuit terminal in the wiper motor harness connector to ground.
  3. Turn the ignition ON.
  4. Operate the windshield wiper/washer switch to the high speed position.

Does the test lamp illuminate?

--

Go to Step 13

Go to Step 8

5

  1. Disconnect the windshield wiper motor connector.
  2. Connect a test lamp from the windshield wiper switch pulse delay signal circuit terminal in the wiper motor harness connector to ground.
  3. Turn the ignition ON.
  4. Press the windshield washer switch.

Does the test lamp illuminate?

--

Go to Step 6

Go to Step 9

6

  1. Disconnect the windshield wiper/washer switch connector.
  2. Measure the resistance through the windshield wiper/washer switch from the pulse delay signal circuit terminal to the accessory voltage supply circuit terminal in the wiper/washer switch connector.
  3. Operate the windshield wiper/washer switch to the following positions:
  4. • MIST
    • LO
    • HI

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

680 ohms

Go to Step 7

Go to Step 11

7

  1. Measure the resistance through the windshield wiper/washer switch from the pulse delay signal circuit terminal to the accessory voltage supply circuit terminal in the wiper/washer switch connector.
  2. Operate the windshield wiper/washer switch through all of the delay positions.

Does the resistance remain within the specified values from high to low as the delay speed is increased?

30K - 450K ohms

Go to Step 13

Go to Step 11

8

Test the windshield wiper motor high speed circuit for an open or high resistance. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 15

Go to Step 11

9

Test the windshield wiper switch pulse delay signal circuit for an open or short to ground. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 15

Go to Step 10

10

Test the accessory voltage supply circuit to the windshield wiper/washer switch for an open or high resistance. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 15

Go to Step 11

11

Inspect for poor connections at the windshield wiper/washer switch. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 15

Go to Step 12

12

Replace the windshield wiper/washer switch. Refer to Turn Signal Multifunction Switch Replacement in Steering Wheel and Column.

Is the repair complete?

--

Go to Step 15

--

13

Inspect for poor connections at the windshield wiper motor. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 15

Go to Step 14

14

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

Is the repair complete?

--

Go to Step 15

--

15

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 3