Subaru Legacy BN/BS (2015-2019) Service Manual: Dtc b1876 open in front seat cushion airbag lh

Subaru Legacy BN/BS (2015-2019) Service Manual / Airbag system (diagnostics) / Diagnostic chart with trouble code / Dtc b1876 open in front seat cushion airbag lh

DIAGNOSIS START CONDITION:

Ignition voltage is 10 V to 16 V.

DTC DETECTING CONDITION:

Open circuit failure (open circuit in rear harness, open circuit in front seat cushion airbag LH, open circuit in airbag CM internal circuit, connector connection failure)

CAUTION:

Before performing diagnosis, refer to “CAUTION” in “General Description”. General Description > CAUTION

WIRING DIAGRAM:

Airbag system Airbag System > WIRING DIAGRAM

STEP	CHECK	YES	NO
1.CHECK POOR CONTACT OF CONNECTORS. Check for poor contact of the connectors between the airbag control module and the seat cushion airbag module LH.	Is there poor contact-	Replace the airbag rear harness along with body harness.	Diagnostic Chart with Trouble Code > DTC B1876 OPEN IN FRONT SEAT CUSHION AIRBAG LH
2.CHECK SEAT CUSHION AIRBAG MODULE. 1) Turn the ignition switch to OFF, disconnect the battery ground cable, and wait for 60 seconds or more. 2) Disconnect the connector (AB5) from the seat cushion airbag module LH, and connect the connector (1D) in the test harness D to connector (AB5). 3) Connect the airbag resistor to connector (3D) in the test harness D. 4) Connect the battery ground terminal and turn the ignition switch to ON.	Does the airbag warning light illuminate for 6 seconds and go off-	Replace the seat cushion airbag module LH. Seat Cushion Airbag Module	Diagnostic Chart with Trouble Code > DTC B1876 OPEN IN FRONT SEAT CUSHION AIRBAG LH
3.CHECK AIRBAG REAR HARNESS (SEAT CUSHION AIRBAG MODULE HARNESS LH) (OPEN CIRCUIT). 1) Turn the ignition switch to OFF, disconnect the battery ground cable, and wait for 60 seconds or more. 2) Disconnect the connector (AB21) from seat belt pretensioner LH. 3) Disconnect the connector (AB19) of the side airbag module LH. 4) Disconnect the connector (AB31) from curtain airbag module LH. 5) Disconnect the airbag resistor from test harness D. 6) Disconnect the connectors (AB6, AB17, AB18) from airbag control module. 7) Connect the connector (1AD) in test harness AD AV to the connectors (AB6, AB17, AB18). 8) Connect the connector (2AD) in test harness AD AV and the connector (1AG) in test harness AG. 9) Measure the resistance between connector (3AG) in the test harness AG and connector (3D) in the test harness D. Connector & terminal (3AG) No. 17 — (3D) No. 3: (3AG) No. 19 — (3D) No. 4:	Is the resistance less than 10 --	Diagnostic Chart with Trouble Code > DTC B1876 OPEN IN FRONT SEAT CUSHION AIRBAG LH	Replace the airbag rear harness along with body harness.
4.CHECK AIRBAG CONTROL MODULE. 1) Connect all connectors. 2) Clear the memory. Clear Memory Mode 3) Perform the Inspection Mode. Inspection Mode 4) Read the DTC. (Current malfunction) Read Diagnostic Trouble Code (DTC)	Is DTC B1876 displayed-	Replace the airbag control module. Airbag Control Module	Diagnostic Chart with Trouble Code > DTC B1876 OPEN IN FRONT SEAT CUSHION AIRBAG LH
5.CHECK FOR ANY OTHER DTC ON DISPLAY. Read the DTC. (Current malfunction) Read Diagnostic Trouble Code (DTC)	Is any other DTC displayed-	Check DTC using “List of Diagnostic Trouble Code (DTC)”. List of Diagnostic Trouble Code (DTC)	Finish the diagnosis.

Dtc b1877 short in front seat cushion airbag lh (to ground)

DIAGNOSIS START CONDITION:Ignition voltage is 10 V to 16 V.DTC DETECTING CONDITION:GND short circuit failure (shorted to ground in main harness, shorted to ground in front seat cushion airbag LH, shor ...

Dtc b1875 short in front seat cushion airbag lh

DIAGNOSIS START CONDITION:Ignition voltage is 10 V to 16 V.DTC DETECTING CONDITION:Shorted between +/− lines (shorted between rear harness lines, shorted between front seat cushion airbag LH lin ...

Other materials:

To install the front cover
CAUTION When reclining the rear seatback, move the front cover backward so that the cover is not damaged. Align the right side of the front cover with the triangle mark before fixing the cover in place. Push the front cover to the right side and shorten the ...