Circuit Description
The power roof module (PRM) provides power and ground for the power roof motor control. The PRM applies power and ground to the roof motor control circuits depending on the desired direction. If the roof module detects a short to ground or an open in a roof motor control circuit, a DTC is set.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC B3973 Moveable Roof Motor Circuits
Conditions for Setting the DTC
The roof module detects a short to ground or an open in a roof motor control circuit.
Action Taken When the DTC Sets
| • | Stores a current DTC B3973 in roof module memory |
| • | Stores a history DTC B3973 in roof module memory |
Conditions for Clearing the DTC
| • | The roof module no longer detects a short to ground or an open in a roof motor control circuit. |
| • | The DTC is cleared using a scan tool. |
Diagnostic Aids
| • | The following conditions may cause an intermittent malfunction: |
| - | There is an intermittent sticking or binding condition in the roof causing the roof motor thermal protection to open. |
| - | The roof motor is shorted internally. |
| • | If the DTC does not reset after the code is cleared, then the problem may be intermittent. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems. |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Sunroof Schematics Connector End View Reference: Power Roof Systems Connector End Views | |||
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
Inspect the roof for a sticking or binding condition. Did you find and correct the condition? | Go to Step 6 | Go to Step 3 | |
3 | Test the power roof motor control circuits for a short to ground or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 6 | Go to Step 4 |
4 | Inspect for poor connections at the harness connector of the power roof 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 6 | Go to Step 5 |
5 |
Did you complete the replacement? | Go to Step 6 | -- |
6 |
Does the DTC reset? | Go to Step 2 | System OK |
