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For 1990-2009 cars only

Diagnostic Aids

The Power Sunroof Actuator Limit Switch can cause the sunroof not to respond correctly to the Power Sunroof Switches with a short to ground or an open. Refer to Testing for Continuity and Wiring Repairs in Wiring Systems. If the circuits test OK, measure the resistance of the Limit Switch, resistance should be indicated in the sunroof positions mentioned in the Power Sunroof Circuit Description , otherwise an open should be indicated. An intermittent or poor connection can also cause the sunroof not to operate normally. Refer to Intermittents and Poor Connections Diagnosis in Wiring Systems.

Test Description

The steps below refer to the test steps in the diagnostic table.

  1. Test for battery voltage (B+) in the supply circuit of the Sunroof Control Module, if voltage is not present, go to the RAP Inoperative table.

Step

Action

Value(s)

Yes

No

1

Was the Diagnostic System Check - Power Sunroof performed?

--

Go to Step  2

Go to Diagnostic System Check - Power Sunroof

2

Verify that the customer complaint is still present.

Does the sunroof operate OK?

--

Go to Diagnostic Aids

Go to Step 3

3

nspect the RAP fuse in the Rear Fuse Block.

Was the fuse blown?

--

Go to Step 18

Go to Step 4

4

  1. Turn OFF the ignition.
  2. Disconnect the Power Sunroof Switches harness connector.
  3. Turn ON the ignition, with the engine OFF.
  4. Measure the voltage between the slide open circuit of the Power Sunroof Slide Switch and the ground circuit of the Power Sunroof Slide Switch.

Is the voltage within the specified range?

10 - 15  V

Go to Step 6

Go to Step 5

5

Measure the voltage between the slide open circuit of the Power Sunroof Slide Switch and a good ground.

Is the voltage within the specified range?

9 - 15  V

Go to Step  15

Go to Step 8

6

Measure the voltage between the other switch input circuits of the Power Sunroof Switches and a good ground.

Is the voltage within the specified range?

10-15 V

Go to Step 7

Go to Step  16

7

Connect a 3 amp fused jumper wire between the slide open circuit of the Power Sunroof Slide Switch and the ground circuit of the Power Sunroof Slide Switch.

Does the sunroof open?

--

Go to Step  21

Go to Step  8

8

  1. Turn OFF the ignition.
  2. Disconnect the Sunroof Control Module harness connector.
  3. Turn ON the ignition, with the engine OFF.
  4. Measure the voltage between the supply circuit of the Sunroof Control Module and the ground circuit of the Sunroof Control Module.

Is the voltage within the specified range ?

10-15 V

Go to Step  10

Go to Step  9

9

Measure the voltage between the supply circuit of the Sunroof Control Module and a good ground.

Is the voltage within the specified range ?

10-15 V

Go to Step  17

Go to Retained Accessory Power (RAP) System Check

10

  1. Turn OFF the ignition.
  2. Disconnect the Power Sunroof Actuator harness connector.
  3. Measure the resistance of each motor control circuit from the Power Sunroof Actuator harness connector to the Sunroof Control Module harness connector.

Is the resistance within the specified range?

1-3 ohms

Go to Step  11

Go to Step  19

11

  1. Reconnect the Sunroof Control Module harness connector.
  2. Turn ON the ignition, with the engine OFF.
  3. Measure the voltage between the slide open circuit of the Power Sunroof Slide Switch and the ground circuit of the Power Sunroof Slide Switch.

Is the voltage within the specified range?

10-15 V

Go to Step  13

Go to Step  12

12

Measure the voltage between the slide open circuit of the Power Sunroof Slide Switch and a good ground.

Is the voltage within the specified range?

10-15 V

Go to Step  15

Go to Step  14

13

  1. Connect a 3 amp fused jumper wire between the slide open circuit of the Power Sunroof Slide Switch and the ground circuit of the Power Sunroof Slide Switch.
  2. Measure the voltage between the motor control circuits of the Sunroof Control Module.

Ignoring polarity, is the voltage within the specified range ?

10-15 V

Go to Step  23

Go to Step  22

14

Test the slide open circuit of the Power Sunroof Slide Switch for an open or high resistance. Refer to Testing for Continuity and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step  27

Go to Step  22

15

Test the ground circuit of the Power Sunroof Slide Switch for an open or high resistance. Refer to Testing for Continuity and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step  27

Go to Step  22

16

Test the switch input circuit of the Power Sunroof Switches for a short to ground. Refer to Testing for Continuity and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step  27

Go to Step  22

17

Repair an open or high resistance in the ground circuit of the Sunroof Control Module. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step  27

--

18

Test the supply circuit of the Sunroof Control Module for a short to ground. Refer to Testing for Continuity and Wiring Repairs to in Wiring Systems.

Did you find and correct the condition?

--

Go to Step  27

Go to Step  20

19

Repair an open or high resistance in the motor control circuits of the Sunroof Control Module. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step  27

--

20

Test the motor control circuits of the Sunroof Control Module for short to ground. Refer to Testing for Continuity and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step  27

Go to Step  22

21

Inspect for a poor connection/terminal tension at the Power Sunroof Switches harness connector. Refer to Intermittents and Poor Connections Diagnosis and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step  27

Go to Step  24

22

Inspect for poor connection/terminal tension at the Sunroof Control Module harness connector. Refer to Intermittents and Poor Connections Diagnosis and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step  27

Go to Step  25

23

Inspect for a poor connection/terminal tension at the Power Sunroof Acruatior harness connector. Refer to Intermittents and Poor Connections Diagnosis and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step  27

Go to Step  26

24

Replace the Power Sunroof Slide Switch. Refer to Sunroof Switch Replacement .

Did you complete the replacement?

--

Go to Step  27

--

25

Replace the Sunroof Control Module. Refer to Power Sunroof Express Module Replacement .

Did you find and correct the condition?

--

Go to Step  27

--

26

Important: Inspect the Power Sunroof Assembly for binding or mechanical failure.

Replace the Power Sunroof Actuator. Refer to Power Sunroof Motor Replacement .

Did you complete the replacement?

--

Go to Step  27

--

27

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step  2