GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Did you review the Wiper/Washer operation and perform the necessary inspections?

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Go to Step 2

Go to Diagnostic Starting Point

2

  1. Turn ON the ignition, with the engine OFF.
  2. Using a test lamp backprobe from the rear window wiper/washer switch CKT 393 (WHT) cavity A to ground.

Does the test lamp illuminate?

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Go to Step 4

Go to Step 3

3

Repair the open in CKT 393 (WHT).

Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

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Go to Step 13

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4

  1. Disconnect the rear window wiper/washer module.
  2. Turn ON the switch.
  3. Connect a test lamp between CKT 391 (GRY) at the rear window wiper/washer module connector cavity B to ground.

Does the test lamp illuminate?

--

Go to Step 6

Go to Step 5

5

Using a test lamp backprobe from the rear window wiper/washer switch CKT 391 (GRY) cavity D to ground.

Does the test lamp illuminate?

--

Go to Step 9

Go to Step 10

6

Connect a test lamp between the rear window wiper/washer module CKT 1450 (BLK) cavity A to CKT 391 cavity B (GRY).

Does the test lamp illuminate?

--

Go to Step 7

Go to Step 8

7

  1. Reconnect the rear window wiper/washer module.
  2. Using a test lamp backprobe from the rear window wiper motor CKT 1440 cavity A to the CKT 293 cavity D.

Does the test lamp illuminate?

--

Go to Step 11

Go to Step 12

8

Repair the open in CKT 1450 (BLK).

Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step 13

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9

Repair the open in CKT 391 (GRY).

Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step 13

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10

Replace the rear window wiper/washer switch.

Refer to Accessory Switch Replacement in Instrument Panel, Gauges, and Console.

Did you complete the replacement?

--

Go to Step 13

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11

Replace the rear window wiper motor.

Refer to Liftgate Wiper Motor Replacement .

Did you complete the replacement?

--

Go to Step 13

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12

Replace the rear window wiper/washer module.

Refer to Liftgate Wiper Motor Replacement .

Did you complete the replacement?

--

Go to Step 13

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13

Operate the system in order to verify the repair.

Did you correct the condition?

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System OK

Go to Step 2