GM Service Manual Online
For 1990-2009 cars only

Wiper/Washer System Check Pulse

Step

Action

Normal Result(s)

Abnormal Result(s)

1

  1. Turn the ignition switch to RUN.
  2. Press the washer switch to ON.

The wipers operate at low speed. The washer sprays the windshield as long as the washer switch is held in the ON position. After releasing the switch, the washer stops and the wipers return to the park position after 2 to 4 sweeps.

    •  Washers Inoperative

2

Set the wiper switch to DELAY (pulse mode).

The wipers make one complete sweep, then pause for 1 to 22 seconds before making the next sweep. The pause time is adjusted by turning the wiper switch through the delay range.

Wipers Delay Mode Inoperative

3

  1. Set the wiper switch to DELAY (Pulse mode).
  2. Press the washer switch to ON.

The washer sprays the windshield as long as the washer switch is held ON. The wipers run at low speed while spraying, and continue for 2 to 4 sweeps after the washer switch is released. The wipers then return to pulse operation.

    •  Washers Inoperative

4

Set the wiper switch to LO.

The wipers run continuously at low speed.

5

Set the wiper switch to HI.

The wipers run continuously at faster speed.

6

Set the wiper switch to OFF.

The wipers return to the park position at low speed.

    •  Wipers Always On

7

Set the wiper switch to MIST, then release.

The wipers make one complete sweep, then return to the park position.

Wiper/Washer System Check Rainsense

Step

Action

Normal Result(s)

Abnormal Result(s)*

1

  1. Turn the ignition switch to RUN.
  2. Press the washer switch on for less than 1.0 second.

The washer sprays the windshield and continues to spray for 2 ½ seconds after the switch is released. The wipers run at low speed while spraying, and continue to run at low speed for two sweeps after the wash cycle is complete, then return to the park position.

    •  Washers Inoperative

2

Turn the wiper switch to LO.

The wipers run continuously at low speed.

3

Turn the wiper switch to HI.

The wipers run continuously at a faster speed.

4

Turn the wiper switch to OFF.

The wipers return to park position at low speed.

    •  Wipers Always On

5

Turn the wiper switch to MIST and release.

Wipers make one complete sweep at low speed, then return to the park position.

6

Turn the wiper switch to the minimum sensitivity (position closest to OFF), AUTO DELAY position.

A single wipe should occur.

Wipers Delay Mode Inoperative

7

Turn the wiper switch to the next-higher sensitivity, AUTO DELAY position. Repeat this step for all sensitivity positions.

A single wipe should occur every time the wiper switch is moved to another automatic position.

Wipers Delay Mode Inoperative

8

    Important: 

       • Clean the windshield with GM cleaning powder (P/N 1050011) or equivalent and rinse thoroughly before performing the test. Use paper towels to dry the windshield before performing the test.
       • The windshield wiper blades must be in good condition.

  1. Turn the wiper switch to the AUTO DELAY position (the minimum sensitivity position which is closest to OFF).
  2. Spray the rainsense module area of the windshield heavily with water for five seconds using a spray bottle or other suitable method.

The wipers run for 15 seconds or less. The wipers SHOULD NOT have any continuous (non-pulsed) wiping after 15 seconds.

The wipers operate continuously for more than 15 seconds. Refer to Wipers Delay Mode Inoperative .

9

  1. Dry the windshield using paper towels.
  2. Turn the wiper switch to maximum sensitivity (position closest to LO), AUTO DELAY position.
  3. Spray the rainsense module area of the windshield heavily with water for five seconds using spray bottle or other suitable method.

The wipers should run continuously (non-pulsed) for 10 seconds or more.

The wipers run in pulse mode within the initial 10 seconds or stop running in 9.0 seconds or less. Refer to Wipers Delay Mode Inoperative .