GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Oldsmobile 🢒 2003 🢒 Alero 🢒 Body and Accessories 🢒 Roof 🢒 Power Sunroof Inoperative

Test Description

The number below refers to the number on the diagnostic table.

  1. Using a jumper wire to short the sunroof limit switch soft stop signal circuit to a good ground, will simulate that the glass is in a position that will allow it to slide in either direction. This will allow any request from the sunroof switch to the sunroof module to supply an output to drive the sunroof motor.

Step

Action

Value(s)

Yes

No

Schematic Reference: Sunroof Schematics

1

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

--

Go to Step 2

Go to Symptoms - Roof

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. Remove the sunroof switch from the headliner.
  2. Disconnect the sunroof switch from the harness connector.
  3. Turn the ignition ON, with the engine OFF.
  4. Connect a jumper wire to sunroof switch low reference circuit at the sunroof switch harness connector.
  5. Depending on the position of the sunroof glass, operate the sunroof system by momentarily connecting the other end of the jumper wire to either of the:
    6. • Sunroof switch open signal circuit
    • Sunroof switch close signal circuit

Does the system operate normally?

--

Go to Step 30

Go to Step 4

4
  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?

4.5-5.5 V

Go to Step 5

Go to Step 12

5

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?

4.5-5.5 V

Go to Step 6

Go to Step 16

6

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?

4.5-5.5 V

Go to Step 7

Go to Step 25

7

Notice: Do not open the sunroof glass past the full open soft stop position. Doing so may damage the sunroof assembly and or the roof top.

  1. Reconnect the sunroof switch to the harness connector.
  2. Connect a jumper wire between the sunroof limit switch soft stop signal circuit at the sunroof module harness connector and a good ground.
  3. Observing the position of the sunroof glass, operate the system by pressing the sunroof switch to slide the glass to the available positions, not to exceed past the full open position.

Did the sunroof glass slide as requested?

--

Go to Step 8

Go to Step 10

8
  1. Remove any jumper wires.
  2. Test the sunroof limit switch range signal 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 40

Go to Step 9

9

Test the sunroof limit 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 40

Go to Step 31

10
  1. Disconnect the sunroof motor harness connector.
  2. Connect a test lamp between the sunroof motor open and motor close control circuits at the sunroof motor harness connector (module side).

Does the test lamp illuminate?

--

Go to Step 38

Go to Step 11

11
  1. Leave the test lamp between the sunroof motor open and motor close control circuits at the sunroof motor harness connector (module side).
  2. While observing the test lamp, press the sunroof switch to the close position then to the open position.

Does test lamp illuminate with each command?

--

Go to Step 33

Go to Step 26

12

Did the reference voltage of the sunroof switch open signal circuit measure near the specified value?

B+

Go to Step 15

Go to Step 13

13

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?

4.5-5.5 V

Go to Step 17

Go to Step 14

14
  1. Disconnect the sunroof module harness connector that contains the ground circuit.
  2. Turn ON the ignition, with the engine OFF.
  3. Measure the sunroof ignition 3 voltage circuit at the sunroof module harness connector to a good ground.

Does the voltage measure near the specified value?

B+

Go to Step 32

Go to Step 19

15

Measure between the sunroof ignition 3 voltage circuit and the ground circuit at the sunroof module harness connector.

Does the voltage measure near the specified value?

B+

Go to Step 32

Go to Step 35

16

Did the reference voltage of the sunroof switch close signal circuit measure near the specified value?

B+

Go to Step 38

Go to Step 18

17

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 40

Go to Step 32

18

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 40

Go to Step 32

19

Test for an open, high resistance or short to ground in the sunroof ignition 3 voltage circuit. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 40

Go to Step 20

20

Measure the ignition 3 voltage supply at the SUNROOF fuse to a good ground.

Does the voltage measure near the specified value?

B+

Go to Step 21

Go to Step 34

21

Inspect for poor connections at the SUNROOF fuse. 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 40

Go to Step 22

22
  1. Reconnect the sunroof switch to the harness connector.
  2. Reconnect the sunroof module harness connector that contains the ground circuit to the sunroof module.
  3. Disconnect the sunroof motor harness connector.
  4. Replace the fuse.
  5. Turn ON the ignition, with the engine OFF.
  6. Measure the sunroof ignition 3 voltage circuit at the sunroof module harness connector to a good ground.

Does the voltage measure near the specified value?

B+

Go to Step 23

Go to Step 38

23
  1. Connect a test lamp between the sunroof motor control circuits.
  2. Operate the sunroof switch to slide the sunroof glass in both directions.

Did the test lamp illuminate in each sunroof switch position?

--

Go to Step 39

Go to Step 24

24
  1. Disconnect the sunroof module harness connector that contains the sunroof motor control circuits.
  2. Test both of the sunroof motor control circuits for a short to ground and for a short to each other. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 40

Go to Step 38

25

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 40

Go to Step 32

26

Connect a test lamp between the sunroof motor open control circuit of the sunroof motor harness connector to B+.

Does the test lamp illuminate?

--

Go to Step 27

Go to Step 29

27
  1. Connect a test lamp between the sunroof motor open circuit to a good ground.
  2. Press the sunroof switch to the open direction for three seconds.

Did the test lamp illuminate?

--

Go to Step 28

Go to Step 32

28

Test the sunroof motor close control 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 40

Go to Step 32

29

Test the sunroof motor open 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 40

Go to Step 32

30

Inspect for poor connections at the sunroof switch and harness connector. 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 40

Go to Step 37

31

Inspect for poor connections 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 38

Go to Step 36

32

Inspect for poor connections 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 40

Go to Step 38

33

Inspect for poor connections at the sunroof 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 40

Go to Step 39

34

Repair the open in the ignition 3 voltage supply circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step 40

--

35

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 40

--

36

Replace the limit switches. Refer to Sunroof Motor/Actuator Replacement .

Did you complete the replacement?

--

Go to Step 40

--

37

Replace the sunroof switch. Refer to Sunroof Switch Replacement .

Did you complete the replacement?

--

Go to Step 40

--

38

Replace the sunroof module. Refer to Sunroof Control Module Replacement .

Did you complete the replacement?

--

Go to Step 40

--

39

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

Did you complete the replacement?

--

Go to Step 40

--

40
  1. Turn OFF the ignition.
  2. Disconnect any jumper wires.
  3. Reconnect all previously disconnected components.
  4. Replace SUNROOF fuse if necessary.
  5. Turn ON the ignition, with the engine OFF.
  6. Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 3