DTC B1805: Short In Passenger's Airbag

Diagnosis start condition:

When the ignition voltage is 10 - 16 V.

DTC detecting condition:

Airbag main harness circuit is shorted.
Airbag module harness circuit (passenger's side) is shorted.
Passenger's airbag module 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.

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

NOTE: Before starting work, prepare two sets of TEST HARNESS AT (98299CA020).

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 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 connector (AB86) from the driver's knee airbag module.
4. Disconnect the connectors (AB41, AB42, AB43) from airbag control module.
5. Connect the connector (1BF) in the test harness BF to the connectors (AB41, AB42, AB43).
6. Disconnect the passenger's airbag module connectors (AB83) and (AB84).
7. Using test harness AT, measure the resistance between terminals in connector (AB83).
  CAUTION: Connect the test harness AT terminal to the connector (AB83) terminal and contact a tester to the test harness AT. Two sets of test harness AT are required.
  
  Connector & terminal
  
  (AB83) No. 1 - (AB83) No. 2:
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. Install the ground terminal to the battery sensor and turn the ignition switch to ON. Ref. to REPAIR CONTENTS>NOTE>BATTERY .
7. Execute the inspection mode. Ref. to AIRBAG (DIAGNOSTICS)>INSPECTION MODE .
8. 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: Replace the airbag control module. Ref. to AIRBAG SYSTEM>AIRBAG CONTROL MODULE>REMOVAL .

No: Go to 4.
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. Execute the inspection mode. Ref. to AIRBAG (DIAGNOSTICS)>INSPECTION MODE .
5. 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: 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.