DTC U0225: Lost Communication With RL Door Power Window

DTC detecting condition: 

Data does not arrive from rear left power window motor.

Trouble symptom: 

LIN communication is not normal.

Wiring diagram: 

Power window system Ref. to WIRING SYSTEM>POWER WINDOW SYSTEM>WIRING DIAGRAM .

Courtesy of SUBARU OF AMERICA, INC.

1. CHECK DTC  .
   1. Turn the ignition switch to OFF.
   2. Turn the ignition switch to ON.
   3. Wait for 5 seconds.
   4. Read the DTC of [Body Control] using the Subaru Select Monitor. Ref. to BODY CONTROL (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .

   Is DTC U0225 displayed? (Current code)

   Yes:  Go to  2.

   No:  Even if DTC is displayed, the circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

   NOTE: In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.
2. CHECK CONTROL MODULE  .

   Using Subaru Select Monitor, confirm that the customization items of [Body Control] correspond to the vehicle. Ref. to BODY CONTROL (DIAGNOSTICS)>CUSTOMIZE .

   Is the customization item [P/W ECU Setting] set to [Four Seat]?

   Yes:  Go to  3.

   No:  Set the customization item corresponding to the vehicle.

3. CHECK HARNESS (OPEN CIRCUIT)  .
   1. Turn the ignition switch to OFF.
   2. Disconnect the body integrated unit connector.
   3. Disconnect the rear power window motor LH connector.
   4. Measure the resistance between body integrated unit connector and rear power window motor LH connector.

      Connector & terminal 

      (i81) No. 2 - (D24) No. 7:

   Is the resistance less than 10 Ω?

   Yes:  Go to  4.

   No:  Repair the open circuit of harness.

4. CHECK HARNESS (SHORT CIRCUIT TO POWER SUPPLY)  .

   Measure the voltage between rear power window motor LH connector and body integrated unit and chassis ground.

   Connector & terminal 

   (D24) No. 7 (+) - Chassis ground (-):

   Is the voltage less than 1 V?

   Yes:  Go to  5.

   No:  Repair the short circuit to power supply in harness.

5. CHECK HARNESS (GROUND SHORT CIRCUIT)  .

   Measure the resistance between rear power window motor LH connector and body integrated unit and chassis ground.

   Connector & terminal 

   (D24) No. 7 (+) - Chassis ground (-):

   Is the voltage 1 MΩ or more?

   Yes:  Replace the body integrated unit. Ref. to SECURITY AND LOCKS>BODY INTEGRATED UNIT .

   No:  Repair the ground short circuit of harness.