GM Service Manual Online
For 1990-2009 cars only

Diagnostic Aids

The sunroof switch open vent signal circuit can cause the sunroof not to respond correctly, if it were an open or a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. If the circuits test OK, an intermittent or poor connection can also cause the sunroof not to operate normally. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Step

Action

Value(s)

Yes

No

Schematic Reference: Sunroof Schematics

Connector End View Reference: Power Roof Systems Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

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Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

Verify that the customer complaint is still present.

Does the sunroof operate OK?

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Go to Diagnostic Aids

Go to Step 3

3

  1. Turn OFF the ignition.
  2. Open the driver door.
  3. Disconnect the sunroof switches harness connector.
  4. Turn ON the ignition, with the engine OFF.
  5. Measure the voltage between the sunroof switch open vent signal circuit of the sunroof vent switch to a good ground.

Is the voltage within the specified range?

10-15 V

Go to Step 4

Go to Step 5

4

Connect a 3-amp fused jumper wire between the sunroof switch open vent signal circuit and the sunroof switch low reference circuit of the sunroof vent switch.

Does the sunroof close?

--

Go to Step 7

Go to Step 6

5

Test the sunroof switch open vent signal circuit of the sunroof vent switch for an open or short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 11

Go to Step 8

6

Test the sunroof switch open vent signal circuit of the sunroof vent switch for an short to B+. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 11

Go to Step 10

7

Inspect for a poor connection at the harness connector of the sunroof switches. 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 11

Go to Step 9

8

Inspect for poor connection at the harness connector of the sunroof 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 11

Go to Step 10

9

Replace the sunroof vent switch. Refer to Sunroof Switch Replacement .

Did you complete the replacement?

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Go to Step 11

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10

Replace the sunroof module. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the replacement?

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Go to Step 11

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11

Operate the system in order to verify the repair.

Did you correct the condition?

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System OK

Go to Step 2