Subaru Legacy BN/BS (2015-2019) Service Manual: Dtc b1638 curtain airbag sensor lh initialization error

Subaru Legacy BN/BS (2015-2019) Service Manual / Airbag system (diagnostics) / Diagnostic chart with trouble code / Dtc b1638 curtain airbag sensor lh initialization error

DIAGNOSIS START CONDITION:

Ignition voltage is 10 V to 16 V.

DTC DETECTING CONDITION:

Curtain airbag sensor LH unit malfunction (sensor type abnormal, sensor unit initialization error)

CAUTION:

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

WIRING DIAGRAM:

NOTE:

For the coupling connector, refer to “WIRING SYSTEM”.

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 curtain airbag sensor LH.	Is there poor contact-	Replace the airbag main harness along with body harness.	Diagnostic Chart with Trouble Code > DTC B1638 CURTAIN AIRBAG SENSOR LH INITIALIZATION ERROR
2.CHECK CURTAIN AIRBAG SENSOR LH. 1) Turn the ignition switch to OFF, disconnect the battery ground cable, and wait for 60 seconds or more. 2) Replace the curtain airbag sensor LH by the curtain airbag sensor RH. Curtain Airbag Sensor > REMOVAL 3) Connect all connectors. 4) Clear the memory. Clear Memory Mode 5) Perform the Inspection Mode. Inspection Mode 6) Read the DTC. (Current malfunction) Read Diagnostic Trouble Code (DTC)	Is DTC B1638 displayed-	Diagnostic Chart with Trouble Code > DTC B1638 CURTAIN AIRBAG SENSOR LH INITIALIZATION ERROR	Replace the curtain airbag sensor LH. Curtain Airbag Sensor > REMOVAL
3.CHECK AIRBAG CONTROL MODULE. 1) Turn the ignition switch to OFF, disconnect the battery ground cable, and wait for 60 seconds or more. 2) Restore the curtain airbag sensors RH and LH back to their original position. Curtain Airbag Sensor > REMOVAL 3) Connect all connectors. 4) Clear the memory. Clear Memory Mode 5) Perform the Inspection Mode. Inspection Mode 6) Read the DTC. (Current malfunction) Read Diagnostic Trouble Code (DTC)	Is DTC B1638 displayed-	Replace the airbag control module. Airbag Control Module > REMOVAL	Diagnostic Chart with Trouble Code > DTC B1638 CURTAIN AIRBAG SENSOR LH INITIALIZATION ERROR
4.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.

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