GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Wiper/Washer Schematics

Connector End View Reference: Wiper/Washer Connector End Views

DEFINITION: The windshield wiper motor operates when the windshield wiper switch is OFF.

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

  1. Turn ON the ignition, with the engine OFF.
  2. Ensure that the windshield wiper switch is OFF.

Does the windshield wiper motor operate?

Go to Step 3

Go to Testing for Intermittent Conditions and Poor Connections

3

Observe the Wiper Delay Input parameter with a scan tool.

Is Wiper Delay Input 0.00 volts?

Go to Step 4

Go to Step 9

4

Observe the Washer Switch parameter with the scan tool.

Is Washer Switch OFF?

Go to Step 5

Go to Step 10

5

Remove the wiper diode.

Does the windshield wiper motor continue to operate?

Go to Step 6

Go to Step 8

6

Remove the wiper micro relay. Refer to Relay Replacement .

Does the windshield wiper motor continue to operate?

Go to Step 7

Go to Step 11

7

Remove the wiper 2 relay. Refer to Relay Replacement .

Does the windshield wiper motor continue to operate?

Go to Step 16

Go to Step 20

8

  1. Install the wiper diode.
  2. Disconnect the windshield wiper switch.

Does the windshield wiper motor continue to operate?

Go to Step 15

Go to Step 19

9

  1. Disconnect the windshield wiper switch.
  2. Observe the Wiper Delay Input parameter with a scan tool.

Is Wiper Delay Input 0.00 volts?

Go to Step 19

Go to Step 13

10

  1. Disconnect the windshield wiper switch.
  2. Observe the Washer Switch parameter with the scan tool.

Is the washer switch OFF?

Go to Step 19

Go to Step 14

11

Probe the windshield wiper switch signal 2 circuit from the body control module (BCM) with a test lamp connected to a good ground.

Does the test lamp illuminate?

Go to Step 12

Go to Step 18

12

  1. Disconnect the underhood fuse block J7 connector.
  2. Probe the windshield wiper switch signal 2 circuit from the BCM with a test lamp connected to a good ground.

Does the test lamp illuminate?

Go to Step 17

Go to Step 20

13

  1. Disconnect the BCM.
  2. Test the windshield wiper switch signal 1 circuit for a short to voltage. Refer to Testing for a Short to Voltage and Wiring Repairs .

Did you find and correct the condition?

Go to Step 22

Go to Step 21

14

  1. Disconnect the BCM.
  2. Test the windshield washer pump control circuit between the BCM and the wiper switch for a short to voltage. Refer to Testing for a Short to Voltage and Wiring Repairs .

Did you find and correct the condition?

Go to Step 22

Go to Step 21

15

  1. Disconnect the underhood fuse block J7 connector.
  2. Test the windshield wiper switch signal 2 circuit between the wiper switch and the fuse block for a short to voltage. Refer to Testing for a Short to Voltage and Wiring Repairs .

Did you find and correct the condition?

Go to Step 22

Go to Step 20

16

  1. Disconnect the underhood fuse block J7 connector.
  2. Test the windshield wiper motor high speed circuit and the windshield wiper motor low speed circuit for a short to voltage. Refer to Testing for a Short to Voltage and Wiring Repairs .

Did you find and correct the condition?

Go to Step 22

Go to Step 20

17

  1. Disconnect the BCM.
  2. Test the windshield wiper switch signal 2 circuit between the BCM and the fuse block for a short to voltage. Refer to Testing for a Short to Voltage and Wiring Repairs .

Did you find and correct the condition?

Go to Step 22

Go to Step 21

18

Replace the wiper micro relay. Refer to Relay Replacement .

Did you complete the replacement?

Go to Step 22

--

19

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

Did you complete the replacement?

Go to Step 22

--

20

Replace the underhood fuse block. Refer to Underhood Electrical Center or Junction Block Replacement .

Did you complete the replacement?

Go to Step 22

--

21

Replace the BCM. Refer to Control Module References for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 22

--

22

  1. Reconnect all disconnected components.
  2. Clear the DTCs with the scan tool.
  3. Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2