DTC B1929: Short In Rear P/T LH

Diagnosis start condition: 

When the ignition voltage is 10 - 16 V.

DTC detecting condition: 

Short malfunction between rear seat belt pretensioner LH circuit and other circuits

Wiring diagram: 

Airbag system Ref. to WIRING SYSTEM>AIRBAG SYSTEM>WIRING DIAGRAM

Courtesy of SUBARU OF AMERICA, INC.

1. CHECK POOR CONTACT OF CONNECTORS  .

   Check for poor contact of the connectors between the airbag control module and Rear seatbelt pretensioner LH.

   Is there poor contact?

   Yes  : Replace the airbag rear harness along with body harness.

   No  : Go to  2.

2. CHECK AIRBAG REAR HARNESS (REAR PRETENSIONER HARNESS LH) (SHORTED BETWEEN LINES)  .
   1. Turn the ignition switch to OFF, and wait for 60 seconds or more after disconnecting the ground terminal from the battery sensor. Ref. to REPAIR CONTENTS>NOTE>BATTERY
   2. Disconnect the connector (AB94) from seat belt pretensioner LH.
   3. Disconnect the connector (AB100) from rear seat belt pretensioner LH.
   4. Disconnect the connector (AB92) from curtain airbag module LH.
   5. Disconnect the connector (AB88) from side airbag module LH.
   6. Disconnect the connectors (AB41, AB42, AB43) from airbag control module.
   7. Connect the connector (1BF) in the test harness BF to the connectors (AB41, AB42, AB43).
   8. Using a probe, measure the resistance between the connector (AB100) and all connector terminals in test harness BF. Ref. to AIRBAG (DIAGNOSTICS)>GENERAL DESCRIPTION>PREPARATION TOOL>HOW TO USE PROBE 
      CAUTION:

      When measuring the resistance, make sure that the probe is inserted from the back side (harness side) of the connector. Also, do not insert the probe forcibly. 

      Connector & terminal 

      (AB100) No. 2 - All terminals in test harness BF (except for (7BF) No. 12):

      (AB100) No. 3 - All terminals in test harness BF (except for (7BF) No. 18):

   Is the resistance 1 MΩ or more?

   Yes  : Go to  3.

   No  : Replace the airbag rear harness along with body harness.

3. CHECK AIRBAG CONTROL MODULE  .
   1. Disconnect the test harness BF from the connectors (AB41, AB42, AB43).
   2. Connect all the connectors other than (AB100) of Rear seatbelt pretensioner LH.
   3. Install the ground terminal to the battery sensor and turn the ignition switch to ON. Ref. to REPAIR CONTENTS>NOTE>BATTERY
   4. Using the Subaru Select Monitor, perform the clear memory of [Airbag]. Ref. to COMMON (DIAGNOSTICS)>CLEAR MEMORY
   5. Execute the inspection mode. Ref. to AIRBAG (DIAGNOSTICS)>INSPECTION MODE 
   6. Read the DTC of [Airbag] using the Subaru Select Monitor. Ref. to AIRBAG (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) 

   Is DTC B1929 displayed? (Current code)

   Yes  : Replace the airbag control module. Ref. to AIRBAG SYSTEM>AIRBAG CONTROL MODULE>REMOVAL

   No  : Replace Rear seatbelt pretensioner LH. Ref. to SEAT BELT SYSTEM>REAR SEAT BELT