Driver Door Module (DDM), (DMFL/R)

U0037-LIN BUS CIRCUIT LOW





For a complete wiring diagram, refer to the Wiring Information.

- When Monitored:
Continuously when the ignition is on.

- Set Condition:
The module detects a short to ground on the LIN Bus circuit.





Diagnostic Test

1. VERIFY DTC IS ACTIVE
1. Turn the ignition on.
2. With the scan tool, read active Door Module DTCs.

Is this DTC active?

Yes

- Go To 2

No

- Manufacturer Code Charts and perform the Stored Lost Communication DTCs diagnostic procedure.

2. CHECK THE LIN BUS CIRCUIT




1. Turn the ignition off.
2. Disconnect the Driver Window/Door Lock Switch C1 connector.
3. Turn the ignition on.
4. Measure the voltage between the (D903) LIN Bus circuit (Cavity 3 or Cavity 6) and the (Q911) Driver Window Switch Sense Return circuit.

Is the voltage above 7.0 volts?

No

- Go To 3

Yes

- Replace the Driver Window/Door Lock Switch.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

3. (D903) LIN BUS CIRCUIT SHORTED TO GROUND




1. Turn the ignition off.
2. Disconnect the Driver Door Module C5 connector.
3. Measure the resistance between Ground and the (D903) LIN Bus circuit in the Door Module C5 connector.

Is the resistance below 10,000 Ohms?

Yes

- Repair the (D903) LIN Bus circuit for a short to the ground.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Go To 4

4. (D903) LIN BUS CIRCUIT SHORTED TO THE (Q911) DRIVER WINDOW SWITCH SENSE RETURN CIRCUIT




1. Measure the resistance between the (D903) LIN Bus circuit and the (Q911) Driver Window Switch Sense Return circuit in the Door Module C5 connector.

Is the resistance below 10,000 Ohms?

Yes

- Repair the (D903) LIN Bus circuit for a short to the (Q911) Driver Window Switch Sense Return circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Replace the Driver Door Module.
- Perform the BODY VERIFICATION TEST. Body Verification Test.