DTC B1831: Open In Curtain Airbag RH Squib Circuit

Diagnosis start condition: 

When the ignition voltage is 10 - 16 V.

DTC detecting condition: 

• Curtain airbag harness RH circuit is open.
• Curtain airbag module RH is faulty.
• Airbag control module is faulty.

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 the curtain airbag module RH.

   Is there poor contact?

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

   No  : Go to  2.

2. CHECK CURTAIN AIRBAG MODULE  .
   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 (AB91) from curtain airbag module RH.
   3. Connect the connector (1N) in the test harness N to the connector (AB91).
   4. Connect the airbag resistor to the connector (2N) of test harness N.
   5. Install the ground terminal to the battery sensor and turn the ignition switch to ON. Ref. to REPAIR CONTENTS>NOTE>BATTERY
   6. Execute the inspection mode. Ref. to AIRBAG (DIAGNOSTICS)>INSPECTION MODE 
   7. Read the DTC of [Airbag] using the Subaru Select Monitor. Ref. to AIRBAG (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) 

   Is DTC B1831 displayed? (Current code)

   Yes  : Go to  3.

   No  : Replace the curtain airbag module RH. Ref. to AIRBAG SYSTEM>CURTAIN AIRBAG MODULE

3. CHECK AIRBAG REAR HARNESS (CURTAIN AIRBAG MODULE HARNESS RH) (OPEN CIRCUIT)  .
   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 (AB93) from seat belt pretensioner RH.
   3. Disconnect the connector (AB95) from the lap seat belt pretensioner RH.
   4. Disconnect the connector (AB99) from Rear seatbelt pretensioner RH.
   5. Disconnect the connector (AB87) from side airbag module RH.
   6. Disconnect the airbag resistor from test harness N.
   7. Disconnect the connectors (AB41, AB42, AB43) from airbag control module.
   8. Connect the connector (1BF) in the test harness BF to the connectors (AB41, AB42, AB43).
   9. Measure the resistance between connector (5BF) in the test harness BF and connector (2N) in the test harness N.

      Connector & terminal 

      (5BF) No. 5 - (2N) No. 1:

      (5BF) No. 1 - (2N) No. 2:

   Is the resistance less than 10 Ω?

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

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