GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 1999 🢒 Riviera 🢒 Body and Accessories 🢒 Roof 🢒 Power Sunroof Does Not Open

Step

Action

Value(s)

Yes

No

1

Did you perform the Power Sunroof System Check ?

--

Go to Step 2

Go to Power Sunroof System Check

2
  1. Turn the ignition switch to the OFF position.
  2. Disconnect the sunroof control module connector C1 and connector C2.
  3. Turn the ignition switch to the RUN position.
  4. Connect the test lamp between the sunroof control module connector C1 terminal C and ground.

Does the test lamp light?

--

Go to Step 3

Go to Step 4

3

Connect the test lamp between the sunroof control module connector C1 terminal C and terminal D.

Does the test lamp light?

--

Go to Step 5

Go to Step 6

4
  1. Inspect the connector C308 terminal A for proper contact.
  2. Inspect the power window/sunroof circuit breaker 25A.
  3. If OK, repair the CKT 141 (BRN) for an open or a short to ground.

Is the repair complete?

--

Go to Power Sunroof System Check

--

5

Using the J 39200 Digital Voltmeter (DVM), inspect for voltage between the sunroof control module connector C1 terminal C and connector C2 terminal 6.

Is voltage present?

--

Go to Step 8

Go to Step 7

6
  1. Inspect the connector C308 terminal C for proper contact.
  2. If OK, repair the CKT 141 (BLK) for an open or a short to ground.

Is the repair complete?

--

Go to Power Sunroof System Check

--

7

Using the J 39200 DVM, inspect for voltage between the sunroof control module connector C1 terminal C and connector C2 terminal 7.

Is voltage present?

--

Go to Step 10

Go to Step 9

8

Repair CKT 100 for a short to ground.

Is the repair complete?

--

Go to Power Sunroof System Check

--

9
  1. Open the sunroof using the following method:
    2. 1.1. Partially lower the headliner.
    1.2. Release the clutch.
    1.3. Manually crank the sunroof using a 4 mm hex wrench.
  2. Using the J 39200 DVM, measure the resistance between the sunroof control module connector C2 terminal 5 and terminal 6.

Is the resistance equal to the specified value?

Infinite

Go to Step 12

Go to Step 11

10

Repair CKT 110 for a short to ground.

Is the repair complete?

--

Go to Power Sunroof System Check

--

11
  1. Inspect for a short between CKT 128 and CKT 100 or CKT 110.
  2. If OK, replace the sunroof switch.

Is the repair complete?

--

Go to Power Sunroof System Check

--

12

Using the J 39200 DVM, measure the resistance between the sunroof control module connector C2 terminal 5 and terminal 7.

Is the resistance equal to the specified value?

Infinite

Go to Step 13

Go to Step 14

13

Using the J 39200 DVM, measure the resistance between the sunroof control module connector C2 terminal 8 and ground.

Is the resistance equal to the specified value?

Infinite

Go to Step 15

Go to Step 16

14
  1. Inspect for a short between CKT 128 and CKT 100 or CKT 110.
  2. If OK, replace the sunroof switch.

Is the repair complete?

--

Go to Power Sunroof System Check

--

15

Using the J 39200 DVM, measure the resistance between the sunroof control module connector C2 terminal 8 and terminal 1.

Is the resistance equal to the specified value?

Infinite

Go to Step 17

Go to Step 18

16
  1. Inspect CKT 132 for a short to ground.
  2. If OK, replace the sunroof motor.

Is the repair complete?

--

Go to Power Sunroof System Check

--

17
  1. Hold the sunroof switch to the CLOSE position.
  2. Using the J 39200 DVM, measure the resistance between the sunroof control module connector C2 terminal 5 and terminal 7.
  3. Hold the sunroof switch to the OPEN position.
  4. Using the J 39200 DVM, measure the resistance between terminal 5 and terminal 7.

Is the resistance less than the specified value in each test?

5 ohms

Go to Step 19

Go to Step 20

18
  1. Inspect for a short between CKT 132 and CKT 133.
  2. If OK, replace the sunroof motor.

Is the repair complete?

--

Go to Power Sunroof System Check

--

19
  1. Close the sunroof.
  2. Connect the fused jumpers between the sunroof control module connector C1 terminal C and terminal B.
  3. Connect the fused jumpers between the sunroof control module connector C1 terminal A and terminal D.

Does the sunroof motor operate?

--

Go to Step 22

Go to Step 21

20
  1. Inspect CKT 100 or CKT 110 and CKT 128 for an open.
  2. Inspect for proper terminal contact at the sunroof switch connectors.
  3. If all of the circuits and connectors are OK, replace the sunroof switch.

Is the repair complete?

--

Go to Power Sunroof System Check

--

21
  1. Inspect CKT 127 and CKT 129 for an open or a short to ground.
  2. If OK, replace the sunroof motor.

Is the repair complete?

--

Go to Power Sunroof System Check

--

22
  1. Inspect the sunroof control module connector C1 for proper terminal contact.
  2. If OK, replace the sunroof control module.

Is the repair complete?

--

Go to Power Sunroof System Check

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