GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2002 🢒 Eldorado 🢒 Body and Accessories 🢒 Roof 🢒 Power Sunroof Inoperative

Step

Action

Value(s)

Yes

No

Schematic Reference: Sunroof Schematics

1

Did you perform the Power Sunroof Diagnostic System Check?

--

Go to Step 2

Go to Diagnostic System Check - Power Sunroof

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

Operate the driver power window switch.

Does the power window operate?

--

Go to Step 4

Go to Retained Accessory Power (RAP) Inoperative in Retained Accessory Power

4
  1. Turn the ignition ON, with the engine OFF.
  2. While listening to the sunroof module, listen for clicking sounds, as the sunroof switch is toggled back and forth between open and close requests.

Does the sunroof module click with each toggle of the sunroof switch?

--

Go to Step 15

Go to Step 5

5

While listening to the sunroof module, listen for clicking sounds as the sunroof switch is momentarily activated forward (close request).

Does the sunroof module click each time the sunroof switch is momentarily activated forward?

--

Go to Step 7

Go to Step 6

6

While listening to the sunroof module, listen for clicking sounds as the sunroof switch is momentarily activated rearward (open request).

Does the sunroof module click each time the sunroof switch is momentarily activated rearward?

--

Go to Step 9

Go to Step 11

7
  1. Disconnect the sunroof switch from the harness connector.
  2. Turn the ignition ON, with the engine OFF.
  3. Momentarily connect a jumper wire between the sunroof low reference circuit and sunroof switch open signal circuit of the sunroof switch harness connector for 3 seconds.

Did the sunroof glass close from the vent position or express open?

--

Go to Step 32

Go to Step 8

8
  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 32

Go to Step 20

9
  1. Disconnect the sunroof switch from the harness connector.
  2. Turn the ignition ON, with the engine OFF.
  3. Connect a jumper wire between the sunroof low reference circuit and sunroof switch close signal circuit of the sunroof switch harness connector for 3 seconds.

Did the sunroof glass close from the open position or open to the vent position?

--

Go to Step 32

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 32

Go to Step 21

11
  1. Disconnect the sunroof switch from the harness connector.
  2. Turn the ignition ON, with the engine OFF.
  3. Connect a jumper wire to the sunroof switch low reference circuit of the sunroof switch harness connector.
  4. Depending on the position of the sunroof glass, try to operate the sunroof by connecting the other end of the jumper wire to the sunroof switch harness connector of either the:
    5. • Sunroof switch open signal circuit
    • Sunroof switch close signal circuit

Does the system operate normally?

--

Go to Step 32

Go to Step 12

12
  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 13

Go to Step 17

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?

B+

Go to Step 14

Go to Step 36

14

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 31

Go to Step 22

15

Important: Observe the circuit colors and location of terminal placement on the sunroof motor prior to any disconnections.

  1. Disconnect both of the sunroof motor control terminals at the sunroof motor.
  2. Connect a test lamp across the sunroof motor control circuits at the terminal connections that went to the sunroof motor.

Does the test lamp illuminate?

--

Go to Step 23

Go to Step 16

16
  1. Leave the test lamp between the sunroof motor control circuits at the terminals of the sunroof motor.
  2. While observing the test lamp, press the sunroof switch for 3 seconds to the close position then for 3 seconds to the open position.

Does test lamp illuminate with each command?

--

Go to Step 34

Go to Step 26

17

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 35

Go to Step 18

18
  1. Disconnect the sunroof module harness connector that contains the RAP relay switch supply voltage circuit.
  2. Measure the RAP relay switch supply voltage circuit at the sunroof module harness connector to a good ground.

Does the voltage measure near the specified value?

B+

Go to Step 19

Go to Step 38

19

Measure between the RAP relay switch supply voltage circuit and the ground circuit at the sunroof module harness connector.

Does the voltage measure near the specified value?

B+

Go to Step 33

Go to Step 39

20

Test for an open or a high resistance 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 43

Go to Step 33

21

Test for an open or a high resistance 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 43

Go to Step 33

22

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

Did you find and correct the condition?

--

Go to Step 43

Go to Step 33

23

Connect a test lamp between the sunroof motor open control circuit terminal that went to the sunroof motor and a good ground.

Does the test lamp illuminate?

--

Go to Step 24

Go to Step 25

24

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

Did you find and correct the condition?

--

Go to Step 43

Go to Step 41

25

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

Did you find and correct the condition?

--

Go to Step 43

Go to Step 41

26

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

Does the test lamp illuminate?

--

Go to Step 27

Go to Step 30

27
  1. Connect a test lamp between the sunroof motor open control circuit terminal to a good ground.
  2. Press the sunroof switch rearward (open direction) for 3 seconds.

Did the test lamp illuminate?

--

Go to Step 28

Go to Step 41

28
  1. Connect a test lamp between the sunroof motor close control circuit terminal to a good ground.
  2. Press the sunroof switch forward (close direction) for 3 seconds.

Did the test lamp illuminate?

--

Go to Step 34

Go to Step 29

29

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 43

Go to Step 33

30

Test the sunroof motor open 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 43

Go to Step 33

31

Measure the continuity between the sunroof switch open and close signal circuits. Refer to Circuit Testing in Wiring Systems.

Does the resistance measure near the specified value?

OL

Go to Step 41

Go to Step 37

32

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 43

Go to Step 40

33

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 43

Go to Step 41

34

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 43

Go to Step 42

35

Test for a short to ground in the sunroof switch open signal circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step 43

Go to Step 41

36

Test for a short to ground in the sunroof switch close signal circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step 43

Go to Step 41

37

Repair a short between the sunroof switch open signal and close signal circuits. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step 43

--

38

Repair an open in the RAP relay switch supply voltage circuit to the sunroof module. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step 43

--

39

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

Did you complete the repair?

--

Go to Step 43

--

40

Replace the sunroof switch. Refer to Sunroof Switch Replacement .

Did you complete the replacement?

--

Go to Step 43

--

41

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

Did you complete the replacement?

--

Go to Step 43

--

42

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

Did you complete the replacement?

--

Go to Step 43

--

43
  1. Turn OFF the ignition.
  2. Disconnect any jumper wires.
  3. Reconnect all previously disconnected components.
  4. Turn the ignition ON, 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