Diagnostic Test

TEST FOR INTERMITTENT CONDITION
Turn the ignition on.

With the scan tool, record and erase DTC's

Press and release the Sunroof Switch in all positions several times.

Wait 30 seconds.

With the scan tool, read DTC's.

Does the scan tool display B1841-SUNROOF OPEN SWITCH INPUT CIRCUIT HIGH?

Yes
1. Go To step 2.
No
1. The conditions that caused this code to set are not present at this time. Check the switch for any binding conditions and using the wiring diagram/schematic as a guide, inspect the wiring and connectors.
SUNROOF SWITCH SHORTED

Fig 1: Checking Sunroof Switch For Short
Courtesy of DAIMLERCHRYSLER CORP.

With the scan tool, erase DTC's.

Turn the ignition off.

Disconnect the Sunroof Switch connector.

Turn the ignition on and wait 30 seconds.

With the scan tool, read DTC's.

Does the scan tool display B1841-SUNROOF OPEN SWITCH INPUT CIRCUIT HIGH?

Yes
1. Go To step 3.
No
1. Replace the Sunroof Switch.
2. Perform BODY VERIFICATION TEST - VER 1. (Refer to BODY VERIFICATION TEST - VER 1) .
(Q3) SUNROOF OPEN SWITCH SENSE CIRCUIT SHORT TO VOLTAGE

Fig 2: Measuring Voltage Of Sunroof Open Switch Sense Circuit
Courtesy of DAIMLERCHRYSLER CORP.

NOTE: To further diagnose the sunroof, it is necessary to lower or remove the headliner.

Turn the ignition off.

Lower the headliner to gain access to the Sunroof Motor/Module connector.

Disconnect the Sunroof Motor/Module connector.

NOTE: Ensure the A-Pillar connector is connected before proceeding.

Turn the ignition on.

Measure the voltage between the (Q3) Sunroof Open Switch Sense circuit and Ground.

Is the voltage above 0.4 volts?

Yes
1. Repair the (Q3) Sunroof Open Switch Sense circuit for a short to voltage.
2. Perform BODY VERIFICATION TEST - VER 1. (Refer to BODY VERIFICATION TEST - VER 1) .
No
1. Go To step 4.
(Q3) SUNROOF OPEN SWITCH SENSE CIRCUIT SHORT TO (Q6) SUNROOF SWITCH SUPPLY CIRCUIT

Fig 3: Measuring Resistance Of Sunroof Open Switch Sense Circuit & Supply Circuit
Courtesy of DAIMLERCHRYSLER CORP.

Turn the ignition off.

Disconnect the A-Pillar connector.

Measure the resistance between the (Q3) Sunroof Open Switch Sense circuit and the (Q6) Sunroof Switch Supply circuit in the Sunroof Motor/Module connector.

Is the resistance below 1000.0 ohms?

Yes
1. Repair the (Q3) Sunroof Open Switch Sense circuit for a short to the (Q6) Sunroof Switch Supply circuit.
2. Perform BODY VERIFICATION TEST - VER 1. (Refer to BODY VERIFICATION TEST - VER 1) .
No
1. Replace the Sunroof Motor/Module.
2. Perform the Sunroof Position Calibration, (Refer to ELECTRICAL/POWER TOP/MOTOR - STANDARD PROCEDURE - SUNROOF POSITION CALIBRATION) . Perform the Excessive Force Limitation Calibration, (Refer to ELECTRICAL/POWER TOP/MOTOR - STANDARD PROCEDURE - EXCESSIVE FORCE LIMITATION CALIBRATION) .
3. Perform BODY VERIFICATION TEST - VER 1. (Refer to BODY VERIFICATION TEST - VER 1) .