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 24K 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 switch through 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 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 16

Go to Step 10

5

  1. Disconnect the windshield wiper motor connector.
  2. Connect a test lamp from the windshield wiper motor accessory voltage supply circuit terminal to ground.
  3. Turn the ignition ON.

Does the test lamp illuminate?

--

Go to Step 6

Go to Step 11

6

  1. Connect a test lamp from the windshield wiper switch signal 2 circuit terminal to ground.
  2. Press the windshield washer switch.

Does the test lamp illuminate?

--

Go to Step 7

Go to Step 12

7

  1. Connect a test lamp from the windshield wiper switch signal 1 circuit terminal to ground.
  2. Operate the windshield wiper/washer switch to the following positions:
  3. • MIST
    • LO
    • HI

Does the test lamp illuminate in the listed switch positions?

--

Go to Step 8

Go to Step 13

8

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

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

24K ohms

Go to Step 9

Go to Step 14

9

  1. Measure the resistance through the windshield wiper/washer switch from the signal 1 circuit terminal to the accessory voltage supply circuit terminal in the switch side 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?

38K - 690K ohms

Go to Step 16

Go to Step 14

10

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

Did you find and correct the condition?

--

Go to Step 18

Go to Step 14

11

Repair the windshield wiper motor accessory voltage supply circuit for an open or high resistance. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Step 18

--

12

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

Did you find and correct the condition?

--

Go to Step 18

Go to Step 14

13

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

Did you find and correct the condition?

--

Go to Step 18

Go to Step 14

14

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

Did you find and correct the condition?

--

Go to Step 18

Go to Step 15

15

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

Is the repair complete?

--

Go to Step 18

--

16

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

Did you find and correct the condition?

--

Go to Step 18

Go to Step 17

17

Replace the windshield wiper motor cover.

Is the repair complete?

--

Go to Step 18

--

18

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 3