DTC U0222: Lost Communication With Driver's Door Power Window

DTC detecting condition :

Data does not arrive from driver's front power window motor.

Trouble symptom :

LIN communication is not normal.

Failure detection pattern :

"Primary" (high-priority diagnosis)

Wiring diagram :

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

Courtesy of SUBARU OF AMERICA, INC.

CAUTION: Before performing diagnosis, refer to "CAUTION" in "General Description". Ref. to BODY CONTROL (DIAGNOSTICS)>GENERAL DESCRIPTION>CAUTION .

CHECK DTC .
1. Turn the ignition switch to OFF.
2. Turn the ignition switch to ON.
3. Wait for 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 U0222 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.
CHECK HARNESS (OPEN CIRCUIT) .
1. Turn the ignition switch to OFF.
2. Disconnect the connector from body integrated unit.
3. Disconnect the connector from the front regulator & motor assembly (driver's side).
4. Using a tester, measure the resistance between the body integrated unit connector and the front regulator & motor assembly (driver's side) connector.
  Connector & terminal
  
  (i83) No. 2 - (Df52) No. 7 :
Is the resistance less than 10 Ω?

Yes : GO TO 3.

No : Repair the open circuit of harness.
CHECK HARNESS (SHORT CIRCUIT TO POWER SUPPLY) .
Using a tester, measure the voltage between the front regulator & motor assembly (driver's side) connector and chassis ground.

Connector & terminal

(Df52) No. 7 (+) - Chassis ground (-) :

Is the voltage less than 1 V?

Yes : GO TO 4.

No : Repair the short circuit to power supply in harness.
CHECK HARNESS (GROUND SHORT CIRCUIT) .
Using a tester, measure the resistance between the front regulator & motor assembly (driver's side) connector and chassis ground.

Connector & terminal

(Df52) No. 7 - Chassis ground :

Is the resistance 1 MΩ or more?

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

No : Repair the ground short circuit of harness.