Subaru Legacy BN/BS (2015-2019) Service Manual: General diagnostic table inspection

Subaru Legacy BN/BS (2015-2019) Service Manual / Keyless access with push button start system (diagnostics) / General diagnostic table inspection

1. IMMOBILIZER SYSTEM

Symptoms	Note
Engine does not start	Diagnostics with Phenomenon > INSPECTION
	Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC B2784 ANTENNA CIRCUIT (PUSH ENGINE SWITCH)
	Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC B278A PUSH ENGINE SWITCH POWER SUPPLY CIRCUIT
	Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC B2785 LIN COMMUNICATION
	Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC B2789 ID CODE BOX COMMUNICATION
	Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC B2790 ID CODE BOX CIRCUIT
	Check the brake switch (except for MT model). Stop Light Switch > INSPECTION Check the clutch switch for MT model. Clutch Switch > INSPECTION
	Check the parking switch signal. AT Shift Lock Solenoid and “P” Range Switch > INSPECTION
	Check the DTC of the ECM.
Cannot register the immobilizer.	Refer to the “REGISTRATION MANUAL FOR IMMOBILIZER”.
Engine does not start with the remote engine starter.	Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC B2779 REMOTE CONTROL ENGINE STARTER COLLATION

2. KEYLESS ACCESS SYSTEM

Symptoms	Reference
All doors cannot be locked/unlocked with keyless access.	Diagnostics with Phenomenon > INSPECTION
Cannot lock with keyless access from the driver’s door.	Diagnostics with Phenomenon > INSPECTION
Cannot lock/unlock from the driver’s door with keyless access.	Diagnostics with Phenomenon > INSPECTION
Cannot unlock from the driver’s door with keyless access.	Diagnostics with Phenomenon > INSPECTION
Cannot unlock from the passenger’s door with keyless access.	Diagnostics with Phenomenon > INSPECTION
Cannot lock/unlock from the passenger’s door with keyless access.	Diagnostics with Phenomenon > INSPECTION
Cannot lock from the passenger’s door with keyless access.	Diagnostics with Phenomenon > INSPECTION
Keyless access passenger room buzzer does not sound.	Diagnostics with Phenomenon > INSPECTION
Keyless access external buzzer does not beep.	Diagnostics with Phenomenon > INSPECTION
Interior collation does not function.	Diagnostics with Phenomenon > INSPECTION
Trunk does not open with the trunk opener button.	Diagnostics with Phenomenon > INSPECTION
Access key lockout protection function in the trunk does not operate.	Diagnostics with Phenomenon > INSPECTION
Rear gate cannot be unlocked with the rear gate opener button.	Diagnostics with Phenomenon > INSPECTION
Rear gate can not be locked when using the rear lock button.	Diagnostics with Phenomenon > INSPECTION

3. STEERING LOCK SYSTEM

Symptoms	Reference
The steering lock cannot be released (Cannot start the engine).	Diagnostics with Phenomenon > INSPECTION
The steering lock does not operate.	Diagnostics with Phenomenon > INSPECTION

4. POWER SUPPLY SWITCHING SYSTEM

Symptoms	Reference
Power will not turn ON (both accessory and ignition).	Diagnostics with Phenomenon > INSPECTION
Power will not turn ON (accessory only).	Diagnostics with Phenomenon > INSPECTION
Power will not turn ON (ignition only).	Diagnostics with Phenomenon > INSPECTION

Electrical component location location

(1)Keyless access CM(8)ECM(14)Center interior antenna(2)Mechanical key(9)Front interior antenna(15)Rear interior antenna(3)Access key(10)TCM (engine type: FB)(16)Rear exterior antenna(4)ID code box(Fo ...

Inspection mode procedure

It is possible to diagnose the DTC by performing the indicated inspection mode. After correcting the DTC, perform a necessary inspection mode and make sure that the function is resumed correctly and t ...

Other materials:

Removal
WARNING:Place “NO OPEN FLAMES” signs near the working area.CAUTION:• Be careful not to spill fuel.• If the fuel gauge indicates that two thirds or more of the fuel is remaining, be sure to drain fuel before starting work to avoid the fuel to spill.• Be careful not to dr ...