DTC B1809: Short In Passenger's Airbag

Diagnosis start condition:

When the ignition voltage is 10 - 16 V.

DTC detecting condition:

Short circuit malfunction between passenger's airbag circuit and other circuit

Wiring diagram:

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

Courtesy of SUBARU OF AMERICA, INC.

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

CHECK POOR CONTACT OF CONNECTORS .
Check for poor contact of the connectors between the airbag control module and the passenger's airbag module.

Is there poor contact?

Yes: Replace the airbag main harness.

No: Go to 2.
CHECK AIRBAG MAIN HARNESS (PASSENGER'S AIRBAG HARNESS) (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 (AB46) from the roll connector.
3. Disconnect the driver's knee airbag module connector (AB86).
4. Disconnect the passenger's airbag module connectors (AB83) and (AB84).
5. Disconnect the connectors (AB41, AB42, AB43) from airbag control module.
6. Connect the connector (1BF) in the test harness BF to the connectors (AB41, AB42, AB43).
7. Measure the resistance between connector (AB83) of the passenger's side airbag module and all connector terminals in the test harness BF.
  CAUTION: Connect the test harness AT terminal to the connector (AB83) terminal and contact a tester to the test harness AT.
  
  Connector & terminal
  
  (AB83) No. 1 - All terminals in test harness BF (except for (9BF) No. 5):
  
  (AB83) No. 2 - All terminals in test harness BF (except for (3BF) No. 4):
Is the resistance 1 MΩ or more?

Yes: Go to 3.

No: Replace the airbag main harness along with body harness.
CHECK AIRBAG CONTROL MODULE .
1. Disconnect all test harnesses.
2. Connect the connectors (AB41, AB42, AB43) to the airbag control module.
3. Connect the connector (AB46) to the roll connector.
4. Connect the passenger's airbag module connector (AB84).
5. Connect the connector (AB86) to the driver's knee airbag module.
6. Using test harness AT, short the terminals No. 1 and No. 2 of connector (AB83).
  Connector & terminal
  
  (AB83) No. 1 - (AB83) No. 2:
7. Install the ground terminal to the battery sensor and turn the ignition switch to ON. Ref. to REPAIR CONTENTS>NOTE>BATTERY .
8. Execute the inspection mode. Ref. to AIRBAG (DIAGNOSTICS)>INSPECTION MODE .
9. Read the DTC of [Airbag] using the Subaru Select Monitor. Ref. to AIRBAG (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .
Is DTC B1805 displayed? (Current code)

Yes: Go to 4.

No: Replace the airbag control module. Ref. to AIRBAG SYSTEM>AIRBAG CONTROL MODULE>REMOVAL .
CHECK PASSENGER'S 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. Connect the passenger's airbag module connector (AB83).
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 B1809 displayed? (Current code)

Yes: Replace the passenger's airbag module. Ref. to AIRBAG SYSTEM>PASSENGER'S AIRBAG MODULE>REMOVAL .

No: Go to 5.
CHECK FOR ANY OTHER DTC ON DISPLAY .
Read the DTC of [Airbag] using the Subaru Select Monitor. Ref. to AIRBAG (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .

Is any other DTC displayed? (Current code)

Yes: Perform the diagnosis for other displayed DTCs. Ref. to AIRBAG (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC)>LIST .

No: Finish the diagnosis.