GM Service Manual Online
For 1990-2009 cars only

Diagnostic Aids

If the power sunroof system should not open to the correct vent position, perform the sunroof motor synchronization procedure. Refer to the appropriate procedure.

Step

Action

Yes

No

Schematic Reference: Sunroof Schematics

Connector End View Reference: Power Roof Systems Connector End Views

DEFINITION: Sunroof system does not stop at vent position or the sunroof switch vent position is inoperative.

1

Did you review the Power Sunroof Description and Operation and perform the necessary inspections?

Go to Step 2

Go to Sunroof Description and Operation

2

Operate the power sunroof.

Does the system operate normally?

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 3

3

  1. Turn ON the ignition, with the engine OFF.
  2. Operate the system to slide the window to the close position.
  3. Press the sunroof switch to the vent position, for 3 seconds.

Did the sunroof window raise upward?

Go to Step 7

Go to Step 4

4

  1. Connect a jumper wire between the sunroof limit switch range signal circuit and the sunroof motor close control circuit at the sunroof switch harness connector.
  2. Press the sunroof switch to the vent position, for 3 seconds.

Did the sunroof window raise upward?

Go to Step 8

Go to Step 5

5

  1. Remove the jumper wires.
  2. Connect a jumper wire between the sunroof limit switch range signal circuit and the ground circuit at the sunroof actuator motor harness connector.
  3. Turn ON the ignition, with the engine OFF.
  4. Press the sunroof switch to the vent position, for 3 seconds.

Did the sunroof window raise upward?

Go to Step 9

Go to Step 6

6

Connect a test lamp between the ground circuit at the sunroof actuator motor harness connector and B+.

Does the test lamp illuminate?

Go to Step 10

Go to Step 11

7

Test the sunroof limit switch range signal circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 14

Go to Step 13

8

Inspect for poor connections at the sunroof 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 14

Go to Step 12

9

Inspect for poor connections at the sunroof actuator 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 14

Go to Step 13

10

Repair the open in the sunroof limit switch range signal circuit. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 14

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11

Repair the open in the ground circuit. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 14

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12

Replace the sunroof switch. Refer to Sunroof Switch Replacement .

Did you complete the replacement?

Go to Step 14

--

13

Important: Perform the sunroof motor synchronization procedure. Refer to the appropriate procedure.

Replace the sunroof actuator motor. Refer to Sunroof Motor/Actuator Replacement .

Did you complete the replacement?

Go to Step 14

--

14

  1. Turn OFF the ignition.
  2. Disconnect any jumper wires.
  3. Connect all previously disconnected components.
  4. Turn ON the ignition, with the engine OFF.
  5. Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3