GM Service Manual Online
For 1990-2009 cars only

Diagnostic Aids

Each door module has a separate battery positive voltage circuit that it uses exclusively for power window motor operation. These circuits are associated with door module harness connectors C1, and, although the circuits are separate, they are connected within the rear fuse block where all are fed by the same PWR WDO circuit breaker. If this circuit opens at a point where the separate branches are all connected, all power windows will be inoperative. A short to ground anywhere in the circuit will open the PWR WDO circuit breaker, which will also cause all power windows to be inoperative. These circuits must not be confused with the battery positive voltage circuits associated with door module harness connectors C3.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. This step determines if this is the correct chart for the symptom.

  2. This step determines if a door module is internally shorted to ground, or the battery positive voltage circuit associated with door module harness connectors C1 is shorted to ground.

Step

Action

Yes

No

Schematic Reference: Power Window Schematics and Door Control Module Schematics

Connector End View Reference: Power Door Systems Connector End Views

DEFINITION: All of the power windows simultaneously fail to operate.

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

  1. Turn ON the ignition, with the engine OFF.
  2. Attempt to operate the power windows from both the driver door switch assembly, and from each one of the window switches mounted to the passenger doors.

Does any window operate?

Go to Symptoms - Doors

Go to Step 3

3

  1. Remove the PWR WDO circuit breaker from the rear fuse block.
  2. Probe the battery supply terminal of the PWR WDO circuit breaker with a test lamp connected to a good ground.

Does the test lamp illuminate?

Go to Step 4

Go to Step 9

4

Connect the test lamp between the 2 fuse block terminals of the PWR WDO circuit breaker.

Does the test lamp illuminate?

Go to Step 6

Go to Step 5

5

Operate any one of the power window switches while observing the test lamp.

Does the test lamp illuminate?

Go to Step 13

Go to Step 8

6

Disconnect each door module, one at a time, while observing the test lamp.

Does the test lamp go out after any module is disconnected?

Go to Step 7

Go to Step 10

7

Inspect for poor connections at the harness connector of the suspect door module. 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 14

Go to Step 11

8

Inspect for poor connections at the harness connector of the rear fuse block. 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 14

Go to Step 12

9

Repair the open in the battery supply circuit of the PWR WDO circuit breaker. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 14

--

10

Repair the short to ground in the battery positive voltage circuit associated with door module harness connectors C1, between the rear fuse block and the door modules. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 14

--

11

Replace the door module that is internally shorted to ground. Refer to Door Control Module Replacement .

Did you complete the replacement?

Go to Step 14

--

12

Replace the rear fuse block. Refer to Rear Electrical Center or Junction Block Replacement .

Did you complete the replacement?

Go to Step 14

--

13

Replace the PWR WDO circuit breaker.

Did you complete the replacement?

Go to Step 14

--

14

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2