GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

Schematic Reference: Sunroof Schematics

Connector End View Reference: Power Roof Systems Connector End Views

1

Did you review the Power Sunroof Description and Operation?

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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

Disconnect the sunroof switch from the harness connector.

Is the sunroof glass in the fully closed position?

--

Go to Step 4

Go to Step 5

4

  1. Turn ON the ignition, with the engine OFF.
  2. Connect a jumper wire to the sunroof switch low reference circuit of the sunroof switch harness connector.
  3. Attempt to slide the sunroof glass towards the open position, by connecting the other end of the jumper wire to the sunroof switch open signal circuit of the sunroof switch harness connector, for 3 seconds.

Did the sunroof glass slide towards the open position?

--

Go to Step 17

Go to Step 6

5

  1. Turn the ignition ON, with the engine OFF.
  2. Connect a jumper wire to the sunroof switch low reference circuit of the sunroof switch harness connector.
  3. Attempt to slide the sunroof glass towards the close position, by connecting the other end of the jumper wire to the sunroof switch close signal circuit of the sunroof switch harness connector, for 3 seconds.

Did the sunroof glass slide towards the close position?

--

Go to Step 22

Go to Step 6

6

  1. Remove the jumper wire.
  2. Measure the reference voltage of the sunroof switch open signal circuit at the sunroof switch harness connector to a good ground.

Does the voltage measure near the specified value?

B+

Go to Step 7

Go to Step 10

7

Measure the reference voltage of the sunroof switch close signal circuit at the sunroof switch harness connector to a good ground.

Does the voltage measure near the specified value?

B+

Go to Step 8

Go to Step 15

8

Measure the reference voltage between the sunroof switch close signal circuit and the sunroof switch low reference circuit at the sunroof switch harness connector.

Does the voltage measure near the specified value?

B+

Go to Step 9

Go to Step 16

9

  1. Disconnect the sunroof module harness connector.
  2. Test for shorts between the sunroof switch signal circuits. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 24

Go to Step 10

10

Measure the reference voltage of the sunroof switch close signal circuit at the sunroof switch harness connector to a good ground.

Does the voltage measure near the specified value?

B+

Go to Step 14

Go to Step 11

11

  1. Disconnect the sunroof module harness connector.
  2. Measure the sunroof accessory voltage circuit at the sunroof module harness connector to a good ground.

Does the voltage measure near the specified value?

B+

Go to Step 12

Go to Step 19

12

Measure between the sunroof battery positive voltage circuit at the sunroof module harness connector to a good ground.

Does the voltage measure near the specified value?

B+

Go to Step 13

Go to Step 20

13

Measure between the sunroof battery positive voltage circuit at the ground circuit at the sunroof module harness connector.

Does the voltage measure near the specified value?

B+

Go to Step 18

Go to Step 21

14

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

Did you find and correct the condition?

--

Go to Step 24

Go to Step 18

15

Test for an open, high resistance or short to ground in the sunroof switch close signal circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 24

Go to Step 22

16

Test the sunroof switch low reference circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 24

Go to Step 18

17

Inspect for a poor connection 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 24

Go to Step 22

18

Inspect for a poor connection at 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 24

Go to Step 23

19

Repair the sunroof accessory voltage circuit for an open, high resistance or a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 24

--

20

Repair the sunroof battery positive voltage signal circuit for an open, high resistance or a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step 24

--

21

Repair the ground circuit of the sunroof module for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step 24

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22

Replace the sunroof switch. Refer to Sunroof Switch Replacement .

Did you complete the replacement?

--

Go to Step 24

--

23

Replace the sunroof module. Refer to Sunroof Motor/Actuator Replacement

Did you complete the replacement?

--

Go to Step 24

--

24

  1. Remove any jumper wires.
  2. Reconnect all previously disconnected components.
  3. Replace RAP fuse if necessary.
  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