GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 2000 🢒 Park Avenue 🢒 Body and Accessories 🢒 Roof 🢒 Power Sunroof Does Not Open

Diagnostic Aids

Refer to Testing for Intermittent Conditions and Poor Connections and Testing for Electrical Intermittents in Wiring Systems.

Step

Action

Value(s)

Yes

No

1

Did you perform the Power Sunroof Diagnostic System Check?

--

Go to Step  2

Go to Diagnostic System Check - Power Sunroof

2
  1. Turn ON the ignition with the engine OFF.
  2. Operate the Power Sunroof Switch to the OPEN position.

Does the sunroof open?

--

Go to Diagnostic Aids

Go to Step 3

3

Test the 20 amp SUNRF fuse for an open.

Is the fuse open?

--

Go to Step  12

Go to Step 4

4
  1. Turn OFF the ignition.
  2. Open the driver door.
  3. Disconnect the sunroof switch.
  4. Turn ON the ignition, with the engine OFF.
  5. Connect a test lamp between the slide input circuit of the sunroof switch harness connector and a good ground.

Does the test lamp illuminate?

--

Go to Step 5

Go to Step 6

5

Using a 3 amp fused jumper wire, jumper the sunroof switch slide input to the ground circuit of the sunroof switch.

Did the power sunroof close?

--

Go to Step 21

Go to Step  7

6

Test the slide input circuit of the sunroof switch for a open circuit or a short to ground. Refer to Circuit Testing in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 26

Go to Step 8

7

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

Did you find and correct the condition?

--

Go to Step 26

Go to Step 11

8
  1. Turn OFF the ignition.
  2. Disconnect the sunroof control module connector.
  3. Turn ON the ignition, with the engine OFF.
  4. Connect a test lamp between the ignition positive voltage circuit of the sunroof control module and a good ground.

Does the test lamp illuminate?

--

Go to Step 9

Go to Step 10

9

Connect a test lamp between the ignition positive voltage circuit and ground circuit of the sunroof control module.

Did the test lamp illuminate?

--

Go to Step 21

Go to Step 18

10

Test the ignition positive voltage feed circuit of the sunroof control module for a short to ground or an open. Refer to Circuit Testing in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 26

Go to Step 21

11

Test the slide input and vent input for a short to each other.

Refer to Circuit Testing in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 26

Go to Step 12

12
  1. Turn OFF the ignition.
  2. Reconnect the sunroof control module.
  3. Reconnect the sunroof switch.
  4. Disconnect the 2 way power sunroof motor .
  5. Turn ON the ignition, with the engine OFF.
  6. Connect a test lamp between the forward input circuit of the sunroof motor and a good ground. Operate the sunroof switch to the CLOSE position.

    7. Does the test lamp illuminate?

--

Go to Step 13

Go to Step 14

13
  1. Connect a test lamp between the forward and reverse input circuit of the sunroof motor.
  2. Operate the sunroof switch to the CLOSE position.

Does the test lamp illuminate?

--

Go to Step 22

Go to Step 19

14

Test the forward input circuit for a short to ground or an open. Refer to Circuit Testing in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 26

Go to Step 15

15
  1. Turn OFF the ignition.
  2. Disconnect the limit switch connector.
  3. Turn ON the ignition, with the engine OFF.
  4. Measure the voltage from the limit switch input of the sunroof control motor to a good ground.

Does the voltage measure near the specified value?

5 V

Go to Step 17

Go to Step 16

16

Test the input circuit of the limit switch for a short to ground or an open. Refer to Circuit Testing in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 26

Go to Step 21

17

Test the ground circuit of the limit switch for a short to voltage or an open. Refer to Circuit Testing in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 26

Go to Step 21

18

Test the ground circuit of the sunroof control module for a short to voltage or an open. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 26

Go to Step 21

19

Test the reverse input circuit for an open circuit. Refer to Circuit Testing in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 26

Go to Step 21

20

Inspect for poor connections at the harness connector of the power 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 26

Go to Step 23

21

Inspect for poor connections at the harness connector of the power sunroof control 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 26

Go to Step 24

22

Inspect for poor connections at the harness connector of the power sunroof motor assembly. 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 26

Go to Step 25

23

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

Did you complete the replacement?

--

Go to Step 26

--

24

Replace the power sunroof control module. Refer to Power Sunroof Express Module Replacement .

Did you complete the replacement?

--

Go to Step 26

--

25

Important: Inspect the power sunroof assembly for binding or mechanical failure.

Replace the power sunroof motor assembly. Refer to Power Sunroof Motor Replacement .

Did you complete the replacement?

--

Go to Step 26

--

26

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 2