Circuit Description
The power roof module (PRM) monitors the power roof motor hall effect sensors during roof motor operation. When the roof module detects that there are no hall sensor pulses or there is a difference of greater than 80 counts between sensor 1 and 2, a DTC is set.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC B3972 Moveable Roof Position Sensor
Conditions for Setting the DTC
The PRM detects that there are no hall sensor pulses or there is a difference of greater than 80 counts between sensor 1 and 2.
Action Taken When the DTC Sets
| • | Stores a current DTC B3972 in roof module memory |
| • | Stores a history DTC B3972 in roof module memory |
Conditions for Clearing the DTC
| • | The roof module no longer detects a current DTC B3972 in roof module memory. |
| • | 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 to be unable to move. |
| - | 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 number below refers to the step number 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 |
2 | Observe the driver information center (DIC). Does the DIC display Open Roof or Close Roof? | Go to Step 5 | Go to Step 3 |
Inspect the roof for a sticking or binding condition. Did you find and correct the condition? | Go to Step 5 | Go to Step 4 | |
4 | Test the hall effect reference, signal, and return circuits for a short to voltage, 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 7 | Go to Step 5 |
5 | 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 7 | Go to Step 6 |
6 |
Did you complete the replacement? | Go to Step 7 | -- |
7 |
Does the DTC reset? | Go to Step 2 | System OK |
