Subaru Legacy BN/BS (2015-2019) Service Manual: Communication for initializing impossible

Subaru Legacy BN/BS (2015-2019) Service Manual / Immobilizer (diagnostics) / Subaru select monitor / Communication for initializing impossible

1. ECM

If the communication with ECM is not possible, refer to ENGINE (DIAGNOSTICS). Basic Diagnostic Procedure > PROCEDURE Basic Diagnostic Procedure > PROCEDURE

2. BODY INTEGRATED UNIT

If the communication with the body integrated unit is not possible, refer to BODY CONTROL SYSTEM (DIAGNOSTICS). Basic Diagnostic Procedure > PROCEDURE

3. IMMOBILIZER CM

DETECTING CONDITION:

• Defective harness

• Power supply circuit malfunction

• Defective immobilizer CM

• Body integrated unit malfunctioning

• Defective CAN communication circuit

• Defective Subaru Select Monitor

TROUBLE SYMPTOM:

Not communicable with Subaru Select Monitor.

WIRING DIAGRAM:

NOTE:

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

Immobilizer system Immobilizer System > WIRING DIAGRAM

STEP	CHECK	YES	NO
1.CHECK FUSE. Check the fuse.	Is there any fault-	Replace the fuse. If the replaced fuse blows out easily, repair the ground short circuit in the harness between the battery and immobilizer CM.	Subaru Select Monitor > COMMUNICATION FOR INITIALIZING IMPOSSIBLE
2.CHECK LAN SYSTEM. Inspect LAN system. Basic Diagnostic Procedure	Is there any fault-	Perform the inspection according to the diagnosis for LAN system.	Subaru Select Monitor > COMMUNICATION FOR INITIALIZING IMPOSSIBLE
3.CHECK HARNESS. 1) Turn the ignition switch to OFF. 2) Disconnect the immobilizer CM connector. 3) Turn the ignition switch to ON. 4) Using a tester, measure the voltage between the immobilizer CM connector and chassis ground. Connector & terminal (i34) No. 2 (+) — Chassis ground (−): (i34) No. 1 (+) — Chassis ground (−):	Is the voltage 10 — 13 V-	Subaru Select Monitor > COMMUNICATION FOR INITIALIZING IMPOSSIBLE	Repair the open circuit of harness between the immobilizer CM connector and fuse.
4.CHECK HARNESS. Using a tester, measure the resistance between the immobilizer CM connector and chassis ground. Connector & terminal (i34) No. 16 — Chassis ground:	Is the resistance less than 1 --	Subaru Select Monitor > COMMUNICATION FOR INITIALIZING IMPOSSIBLE	Repair the open circuit of harness between the immobilizer CM connector and chassis ground.
5.CHECK IMMOBILIZER CM. 1) Turn the ignition switch to OFF. 2) Connect the immobilizer CM connector. 3) Perform communication with the immobilizer CM.	Is communication possible-	The circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again. NOTE: In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.	Replace the immobilizer CM. Immobilizer Control Module

Operation

For operation procedures, refer to “Application help”. ...

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