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For 1990-2009 cars only

Diagnostic Aids

    • The symptoms listed directly below are considered to be erratic and can usually be attributed to a failure of one of the sunroof switch data signal circuits. The failure may occur to the hard wire, external part of the circuit, or it may occur to the part of the circuit that is within the related component, i.e. sunroof switch or sunroof motor/actuator. If the failure is within the related component, the component must be replaced.
       - Power sunroof and power sunshade operate only to certain positions
       - Power sunroof and power sunshade open or close to the wrong position
    • The power sunroof is opened and closed by using the power sunroof switch. When the sunroof opens, the power sunshade opens with it. The sunshade also closes when the sunroof closes, however, the sunshade will only close to the first closed position. From this position, the closing of the sunshade must be completed by using the sunshade switch. The power sunroof motor/actuator monitors the positions of the both the sunroof and the sunshade and limits the opening of the sunroof and the closing of the sunshade based upon the current positions of the sunroof and the sunshade. The power sunroof motor/actuator will not allow the sunroof glass to be opened more than the sunshade panel.
    • If a power sunroof switch data signal circuit shorts to voltage, it is likely that the circuit will open permanently inside the switch. If you are replacing the switch due to an open internal circuit, be sure to test the corresponding external circuit for a short to battery.
    • The power sunroof motor/actuator assembly contains the sunroof electronic control module. The individual components are not serviced separately.
    •  The power sunshade motor/actuator assembly contains the sunshade electronic control module. The individual components are not serviced separately.
    • The power sunroof motor/actuator is also known as the power sunroof master control module.
    • The power sunshade motor/actuator is also known as the power sunroof slave module.

       Important: If the power sunroof and power sunshade both operate normally from the power sunroof switch, but the power sunshade is inoperative from the power sunshade switch, refer to Power Sunshade Inoperative .

Test Description

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

  1. This step verifies that you are using the correct table for the symptom.

  2. This step, along with steps 7, 8, 9, 10, and 11, tests the internal circuitry of the power sunroof switch. The power sunroof switch test table may be used in conjunction with these steps to assist in your diagnosis. Refer to Power Sunroof Switch Test .

Step

Action

Yes

No

Schematic Reference: Sunroof Schematics

Connector End View Reference: Master Electrical Component List

DEFINITION: The vehicle is equipped with RPO C3Y, panoramic sunroof. The power sunroof and the power sunshade are partially operational.

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

Perform the following actions in order to verify the complaint.

    • Attempt to operate the sunroof through its full range of functions.
    • Attempt to operate the sunshade through its full range of functions.

Do the sunroof and sunshade operate normally?

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

3

Do the sunroof and sunshade operate at all?

Go to Step 4

Go to Symptoms - Roof

4

  1. Perform the sunroof re-initialization. Refer to Sunroof Control Module Programming and Setup .
  2. Attempt to operate the sunroof and the sunshade through their full range of functions.

Do the sunroof and sunshade operate normally?

Go to Step 18

Go to Step 5

5

  1. Turn OFF the ignition.
  2. Disconnect the harness connector of the sunroof switch.
  3. Turn ON the ignition, with the engine OFF.
  4. With a volt meter connected to a good ground, probe the following circuits of the harness connector:
  5. • Sunroof switch data 1 signal circuit
    • Sunroof switch data 2 signal circuit
    • Sunroof switch data 3 signal circuit

Does the volt meter display near battery voltage for all 3 circuits?

Go to Step 6

Go to Step 12

6

  1. Turn OFF the ignition.
  2. Leave the sunroof switch harness connector disconnected.
  3. Disconnect the harness connector of the sunroof motor/actuator.
  4. Turn ON the ignition, with the engine OFF.
  5. With a volt meter, measure the following circuits for voltage:
  6. • Sunroof switch data 1 signal circuit
    • Sunroof switch data 2 signal circuit
    • Sunroof switch data 3 signal circuit

Is battery voltage present on any of the data signal circuits?

Go to Step 15

Go to Step 7

7

  1. Leave the sunroof switch and sunroof motor/actuator harness connectors disconnected .
  2. Place the sunroof switch in the number 0 (closed) position.
  3. Test the sunroof switch for continuity between the following pins:
  4. • Pins 4 and 1
    • Pins 4 and 2
    • Pins 4 and 5

There should be continuity only between pins 4 and 5.

Are the test results as they should be?

Go to Step 8

Go to Step 14

8

  1. Place the sunroof switch in the number 1 (vent) position.
  2. Test the sunroof switch for continuity between the following pins:
  3. • Pins 4 and 1
    • Pins 4 and 2
    • Pins 4 and 5

There should be continuity between pins 4 and 5, and between pins 4 and 1. There should be no continuity between pins 4 and 2.

Are the test results as they should be?

Go to Step 9

Go to Step 14

9

  1. Place the sunroof switch in the number 2 position.
  2. Test the sunroof switch for continuity between the following pins:
  3. • Pins 4 and 1
    • Pins 4 and 2
    • Pins 4 and 5

There should be continuity only between pins 4 and 1.

Are the test results as they should be?

Go to Step 10

Go to Step 14

10

  1. Place the sunroof switch in the number 3 position.
  2. Test the sunroof switch for continuity between the following pins:
  3. • Pins 4 and 1
    • Pins 4 and 2
    • Pins 4 and 5

There should be continuity between pins 4 and 1, and between pins 4 and 2. There should be no continuity between pins 4 and 5.

Are the test results as they should be?

Go to Step 11

Go to Step 14

11

  1. Place the sunroof switch in the number 4 (full open) position.
  2. Test the sunroof switch for continuity between the following pins:
  3. • Pins 4 and 1
    • Pins 4 and 2
    • Pins 4 and 5

There should be continuity between pin 4 and each one of the other three pins.

Are the test results as they should be?

Go to Step 13

Go to Step 14

12

Test the appropriate sunroof switch data signal circuit for the following:

    • A short to ground
    • An open
    • A high resistance

Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 18

Go to Step 13

13

Inspect for poor connections at the harness connector of 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 18

Go to Step 16

14

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

Did you find and correct the condition?

Go to Step 18

Go to Step 17

15

Important: If the sunroof switch data 1, data 2, or data 3 signal circuit is shorted to voltage, the condition may have opened the circuit inside the sunroof switch. Once the short to voltage has been repaired, test the switch before installation. Refer to Power Sunroof Switch Test .

Repair the appropriate sunroof switch data signal circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs .

Did you complete the repair?

Go to Step 18

--

16

Replace the sunroof motor/actuator. Refer to Control Module References for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 18

--

17

Replace the sunroof switch. Refer to Sunroof Switch Replacement .

Did you complete the replacement?

Go to Step 18

--

18

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2