GM Service Manual Online
For 1990-2009 cars only

Test Description

The numbers below refer to the steps on the diagnostic table.

  1. If the sunroof switch open signal circuit is jumpered first, this may cause the window to express open. Jumpering the sunroof switch close signal circuit will halt the express open feature. To close the sunroof glass the sunroof switch close signal circuit will need to be jumpered again, and maintained to continue to close the sunroof glass.

  2. Disconnecting the connector to the sunroof opening position switch (SOPS), and shorting the SOPS vent signal circuit to the SOPS low reference circuit, will simulate that the glass is in a position other than full vent or full open position. This will allow any request from the sunroof switch to supply an output to drive the motor for testing the status of the SOPS.

  3. Checking the sunroof motor open and close output circuits, when idle both should be at ground potential.

Step

Action

Values

Yes

No

Schematic Reference: Sunroof Schematics

Connector End View Reference: Sunroof Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

--

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

Operate the power sunroof.

Does the system operate normally?

--

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

3

  1. Turn ON the ignition, with the engine OFF.
  2. Operate the power window left front (LF) window switch.

Does the LF power window system operate normally?

--

Go to Step 4

Go to Retained Accessory Power (RAP) Inoperative

4

  1. Remove the sunroof switch from the headliner.
  2. Disconnect the sunroof switch from the harness connector.
  3. Connect a fused jumper wire to the low reference circuit of the sunroof switch connector.
  4. Depending on the position of the sunroof glass, try to operate the glass by connecting the other end of the jumper wire for 3 seconds to either of the following:
  5. • Sunroof switch open signal circuit
    • Sunroof switch close signal circuit

Does the system operate normally?

--

Go to Step 40

Go to Step 5

5

  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 6

Go to Step 20

6

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 7

Go to Step 25

7

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 8

Go to Step 30

8

  1. Disconnect the harness connector at the sunroof opening position switch (SOPS).
  2. Measure the reference voltage of the SOPS range signal circuit at the SOPS harness connector to a good ground. Refer to Circuit Testing .

Does the voltage measure near the specified value?

4.5-5.5 V

Go to Step 9

Go to Step 11

9

Measure the reference voltage of the SOPS soft stop signal circuit at the SOPS harness connector to a good ground. Refer to Circuit Testing .

Does the voltage measure near the specified value?

4.5-5.5 V

Go to Step 10

Go to Step 13

10

Measure the reference voltage between the SOPS soft stop signal circuit and the SOPS low reference circuit at the SOPS harness connector. Refer to Circuit Testing .

Does the voltage measure near the specified value?

4.5-5.5 V

Go to Step 17

Go to Step 15

11

Test the SOPS range signal circuit for an open, high resistance, or a short to ground. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 53

Go to Step 12

12

Inspect for a poor connection in the SOPS range signal circuit. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

--

Go to Step 53

Go to Step 51

13

Test the SOPS soft stop signal circuit for an open, high resistance, or a short to ground. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 53

Go to Step 14

14

Inspect for a poor connection in the SOPS soft stop signal circuit. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

--

Go to Step 53

Go to Step 51

15

Test the SOPS low reference circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 53

Go to Step 16

16

Inspect for a poor connection in the SOPS low reference circuit. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

--

Go to Step 53

Go to Step 51

17

Notice: Avoid having the sunroof glass slide past the full open position. Since the Sunroof Opening Position Switch (SOPS) will be disconnected and jumpered, their is no way for the sunroof Control module to understand what position the glass is in or moving too. Since the sunroof control module does not see any input changes from the limit switches, the sunroof glass cannot soft stop, which can cause the glass to exceed past the full open position, possibly damaging the sunroof assembly and or the roof.

  1. Reconnect the sunroof switch to the harness connector.
  2. Connect a jumper wire between the SOPS soft stop signal circuit and the SOPS low reference circuit at the SOPS harness connector.
  3. Observing the position of the sunroof glass, operate the system by pressing the sunroof switch to slide the glass to the available positions (open then closed or closed then open), not exceeding the full open position.

Did the sunroof glass slide as requested?

--

Go to Step 44

Go to Step 18

18

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

Does the test lamp illuminate?

--

Go to Step 32

Go to Step 19

19

  1. Leave the test lamp between the sunroof motor open and motor close control circuits at the harness connector (module side).
  2. While observing the test lamp, press the sunroof switch for 3 seconds to the close position then to the open position.

Does test lamp illuminate with each command?

--

Go to Step  42

Go to Step  35

20

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

B+

Go to Step 22

Go to Step 21

21

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 26

Go to Step 23

22

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 39

Go to Step 24

23

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

Does the voltage measure near the specified value?

B+

Go to Step 41

Go to Step 45

24

  1. Disconnect the sunroof control module harness connector that contains the sunroof accessory voltage circuit.
  2. Measure between the sunroof accessory voltage circuit and the ground circuit at the sunroof control module harness connector.

Does the voltage measure near the specified value?

B+

Go to Step 41

Go to Step 48

25

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

B+

Go to Step 29

Go to Step 27

26

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

Did you find and correct the condition?

--

Go to Step 53

Go to Step 41

27

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

Did you find and correct the condition?

--

Go to Step 53

Go to Step 28

28

Inspect for a poor connection in the sunroof switch close signal circuit. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

--

Go to Step 53

Go to Step 51

29

Test the sunroof switch close signal circuit for a short to B+. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 53

Go to Step 51

30

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

Did you find and correct the condition?

--

Go to Step 53

Go to Step 31

31

Inspect for a poor connection in the sunroof switch low reference circuit. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

--

Go to Step 53

Go to Step 51

32

Connect a test lamp between the sunroof motor/actuator open control circuit at the harness connector (module side) and a good ground.

Does the test lamp illuminate?

--

Go to Step 33

Go to Step 34

33

Test the sunroof motor/actuator open control circuit for a short to B+. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 53

Go to Step 51

34

Test the sunroof motor/actuator close control circuit for a short to B+. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 53

Go to Step 51

35

Connect a test lamp between the sunroof motor/actuator open control circuit to B+.

Does the test lamp illuminate?

--

Go to Step 36

Go to Step 38

36

  1. Connect a test lamp between the sunroof motor/actuator open control circuit to a good ground.
  2. Press the sunroof switch to the open direction.

Did the test lamp illuminate?

--

Go to Step 37

Go to Step 47

37

Test the sunroof motor/actuator close control circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 53

Go to Step 41

38

Test the sunroof motor/actuator open control circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 53

Go to Step 43

39

Test the sunroof switch open signal circuit for a short to B+. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 53

Go to Step 51

40

Inspect for a poor connection at the sunroof switch and harness connector. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

--

Go to Step 53

Go to Step 50

41

Inspect for a poor connection at the sunroof control module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

--

Go to Step 53

Go to Step 51

42

Inspect for poor connections at the sunroof motor/actuator. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

--

Go to Step 53

Go to Step 52

43

Inspect for poor connections in the sunroof motor/actuator open control circuit. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

--

Go to Step 53

Go to Step 51

44

Inspect for a poor connections at the SOPS module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

--

Go to Step 53

Go to Step 49

45

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

Did you complete the repair?

--

Go to Step 53

Go to Step 46

46

Test both of the sunroof motor/actuator control circuits for a short to ground. Refer to Circuit Testing and Wiring Repairs .

Did you complete the repair?

--

Go to Step 53

Go to Step 47

47

  1. Disconnect the harness connector at the SOPS module.
  2. Disconnect the harness connector to the sunroof motor/actuator.
  3. Disconnect the harness connectors of the sunroof control module.
  4. Test for continuity between all the sunroof system circuits at the sunroof/control module connectors. Refer to Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 53

Go to Step 51

48

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

Did you complete the repair?

--

Go to Step 53

--

49

Replace the SOPS module. Refer to Sunroof Opening Position Switch Replacement .

Did you complete the repair?

--

Go to Step 53

--

50

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

Did you complete the replacement?

--

Go to Step 53

--

51

Replace the power sunroof control module. Refer to Control Module References for replacement, setup, and programming.

Did you complete the replacement?

--

Go to Step 53

--

52

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

Did you complete the replacement?

--

Go to Step 53

--

53

  1. Turn OFF the ignition.
  2. Disconnect any jumper wires.
  3. Reconnect all previously disconnected components.
  4. Replace SUN RF fuse if necessary.
  5. Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 3