GM Service Manual Online
For 1990-2009 cars only

Test Description

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

  1. This step will test the if the sunroof will slide to the open position. If it opens, then inspect the sunroof limit switch position-LS2 for a stuck switch causing an intermittent short to ground.

  2. Testing for a short to ground in the sunroof limit switch position 2-LS2 circuit or a stuck/closed limit switch.

Step

Action

Value(s)

Yes

No

Schematic Reference: Sunroof Schematics

Connector End View Reference: Power Roof Systems Connector End Views

DEFINITION: Sunroof only slides between the closed and vent positions, does not slide to open position.

1

Did you perform the A Diagnostic System Check - Power Sunroof?

--

Go to Step 2

Go to Diagnostic System Check - Power Sunroof

2

Operate the power sunroof to the open position.

Does the system operate normally?

--

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 3

3

  1. Turn the ignition ON, with the engine OFF.
  2. Activate the sunroof switch to close the sunroof.
  3. Measure the voltage between the sunroof limit switch position 2-LS2 circuit and sunroof limit switch low reference circuit at the sunroof control module harness connector.

Does the voltage measure near the specified value?

5 V

Go to Step 6

Go to Step 4

4

  1. Disconnect the harness connector to the sunroof opening position switch.
  2. Test the sunroof limit switch position 2-LS2 circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 7

Go to Step 5

5

Replace the sunroof opening position switch. Refer to Sunroof Opening Position Switch Replacement .

Did you complete the replacement?

--

Go to Step 7

--

6

Replace the sunroof control module. Refer to Sunroof Motor/Actuator Replacement .

Did you complete the replacement?

--

Go to Step 7

--

7

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 3