DTC U0223: Lost Communication With Passenger's Door Power Window

DTC detecting condition: 

Data does not arrive from passenger's front 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 at least 10 seconds.
   4. Read the DTC of [Body Control] using the Subaru Select Monitor. Ref. to BODY CONTROL (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .

   Is DTC U0223 displayed? (Current malfunction)

   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 BODY INTEGRATED UNIT CUSTOMIZATION  .

   Using Subaru Select Monitor, make sure the [Customize] setting values of [Body Control] correspond to the vehicle.

   Is [P/W ECU Setting] set to [D/P seat] or [Four Seat]?

   Yes  : Go to  3.

   No  : Change the setting value to [Four Seat].

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

      Connector & terminal 

      (i83) No. 2 - (Df51) 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)  .
   1. Turn the ignition switch to ON.
   2. Measure the voltage between front power window motor (passenger's) connector and chassis ground.

      Connector & terminal 

      (Df51) 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)  .
   1. Turn the ignition switch to OFF.
   2. Measure the resistance between front power window motor (passenger's) connector and chassis ground.

      Connector & terminal 

      (Df51) No. 7 - Chassis ground:

   Is the resistance 1 MΩ or more?

   Yes  : Go to  6.

   No  : Repair the ground short circuit of harness.

6. CHECK DTC  .
   1. Turn the ignition switch to ON.
   2. Wait for at least 10 seconds.
   3. Read the DTC of [Body Control] using the Subaru Select Monitor. Ref. to BODY CONTROL (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .

   Is more than one of DTC U0222, U0223, U0224, U0225, or U1822 displayed? (Current malfunction)

   Yes  : Replace the body integrated unit. Ref. to BODY CONTROL/COMMUNICATION SYSTEM>BODY INTEGRATED UNIT .

   No  : Replace the front regulator & motor assembly (passenger's side). Ref. to GLASS/WINDOWS/MIRRORS>FRONT REGULATOR AND MOTOR ASSEMBLY .