DTC B2B31: RR Door Power Window Manual Up Switch Stuck

DTC detecting condition: 

When UP Terminal Input ON is received for 20±1 seconds or longer.

Trouble symptom: 

• When the power window sub-switch is operated, the rear right window does not work.
• When the power window sub-switch is operated, the rear right window rolls down only in manual down operation, or inches up. (Inch up: Operating the switch rolls up the window about 10 mm only)

Wiring diagram: 

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

Courtesy of SUBARU OF AMERICA, INC.

1. CHECK REAR POWER WINDOW SUB-SWITCH UNIT  .

   Perform unit inspection of rear power window sub-switch RH. Ref. to GLASS/WINDOW/MIRRORS>POWER WINDOW CONTROL SWITCH .

   Is the check result OK?

   Yes:  Go to  2 .

   No:  Replace the rear power window sub-switch RH. Ref. to GLASS/WINDOW/MIRRORS>POWER WINDOW CONTROL SWITCH .

2. CHECK HARNESS (OPEN CIRCUIT)  .
   1. Disconnect the rear power window sub-switch RH connector.
   2. Disconnect the rear regulator and motor assembly RH connector.
   3. Disconnect the body integrated unit connector.
   4. Using a tester, measure the resistance between the rear power window sub-switch RH connector and the rear regulator and motor assembly RH connector.

      Connector and terminal 

      (Dr31) No. 6 - (Dr41) No. 8:

   Is the resistance less than 1 Ω?

   Yes:  Go to  3 .

   No:  Repair the open circuit of harness between the rear power window sub-switch RH connector and the rear regulator and motor assembly RH connector.

3. CHECK HARNESS (GROUND SHORT CIRCUIT)  .

   Using a tester, measure the resistance between the rear power window sub-switch RH connector and chassis ground.

   Connector and terminal 

   (Dr31) No. 6 - Chassis ground:

   Is the resistance 1 MΩ or more?

   Yes:  Go to  4 .

   No:  Repair the short circuit to ground in harness between the rear power window sub-switch RH connector and the rear regulator and motor assembly RH connector.

4. CHECK HARNESS (SHORT CIRCUIT TO POWER SUPPLY)  .
   1. Turn the ignition switch to ON.
   2. Using a tester, measure the voltage between the rear power window sub-switch RH connector and chassis ground.

      Connector and terminal 

      (Dr31) No. 6 (+) - Chassis ground (-):

   Is the voltage less than 1 V?

   Yes:  Go to  5 .

   No:  Repair the short circuit to power supply in the harness between the rear power window sub-switch RH connector and the rear regulator and motor assembly RH connector.

5. ACTIVE TEST  .

   Using the Subaru Select Monitor, check the following items in the [Active Test] of [Power Window (Rear Right)]. Ref. to Power Window (Diagnostics)>Active Test .

   • Power Window Operation Test

   Does the window roll up and down?

   Yes:  Go to  6 .

   No:  Replace the rear regulator and motor assembly RH. Ref. to GLASS/WINDOW/MIRRORS>REAR REGULATOR AND MOTOR ASSEMBLY .

6. CHECK DTC  .

   Read the DTC of [Power Window (Rear Right)] using the Subaru Select Monitor. Ref. to Power Window (Diagnostics)>Diagnostic Trouble Code (DTC) .

   Is DTC B2B31 displayed? (Current malfunction)

   Yes:  Replace the rear regulator and motor assembly RH. Ref. to GLASS/WINDOW/MIRRORS>REAR REGULATOR AND MOTOR ASSEMBLY .

   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.