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Basic Diagnostic Procedure: Procedure

WARNING: This page is about a different car, the 2016 Subaru Outback and 2016 Subaru Legacy. However, it is still accessible from the selected car via links, so may be relevant.

CAUTION:

Remove foreign matter (dust, water, oil, etc.) from each control module connector during removal and installation.
Registration of immobilizer may be needed after the replacement of control modules, etc. For detailed procedure, refer to the "REGISTRATION MANUAL FOR IMMOBILIZER".

NOTE:

To check harness for open or short circuits, shake the suspected trouble spot or connector.
Check List for Interview < Ref. to CHECK LIST FOR INTERVIEW . >

DIAGNOSTICS PROCEDURE

Step	Check	Yes	No
1 CHECK PRE-INSPECTION. Ask the customer when and how the trouble occurred using the interview check list. < Ref. to CHECK LIST FOR INTERVIEW . >	Did you interview the customer?	Go to step 2 .	Interview the customer.
2 BASIC INSPECTION (CAN DIAGNOSTIC IS NOT USED). Check components which might affect CAN communication problem. < Ref. to INSPECTION WITHOUT USING CAN DIAGNOSTIC , INSPECTION, General Description. >	Is the component that might affect CAN communication problem normal?	Go to step 3 .	Repair or replace each component.
3 CHECK COMMUNICATION FOR INITIALIZING. Communicate with the all systems by connecting the Subaru Select Monitor.	Is the communication for initializing finished for all modules?	Go to step 4 .	Check the error of communication for initializing. < Ref. to COMMUNICATION FOR INITIALIZING IMPOSSIBLE , Subaru Select Monitor. >
4 BASIC INSPECTION (CAN DIAGNOSTIC IS USED). Check components which might affect CAN communication problem. < Ref. to INSPECTION USING CAN DIAGNOSTIC , INSPECTION, General Description. >	Is the component that might affect CAN communication problem normal?	Go to step 5 .	Repair or replace each component.
5 CHECK DTC. Start the engine and read all DTCs. NOTE: When the engine does not start, perform the diagnosis for the engine start malfunction. < Ref. to DIAGNOSTICS FOR ENGINE STARTING FAILURE . > < Ref. to DIAGNOSTICS FOR ENGINE STARTING FAILURE . > Record all DTCs, time stamp and freeze frame data. NOTE: For time stamp, refer to "TIME STAMP" of General Description. < Ref. to TIME STAMP , CAUTION, General Description. >	Is DTC U**** displayed?	Go to step 6 .	Go to step 7 .
6 CHECK DTC. Perform the inspection using the DTC check sheet. < Ref. to CHECK USING THE DTC CHECK SHEET , LIST, List of Diagnostic Trouble Code (DTC). > Using the Subaru Select Monitor, read all DTCs.	Is DTC U**** displayed?	Go to step 8 .	Go to step 7 .
7 PERFORM GENERAL DIAGNOSTICS. Inspect using the "General Diagnostic Table". < Ref. to GENERAL DIAGNOSTIC TABLE . >	Is result of inspection OK?	LAN system is normal.	Go to step 8 .
8 PERFORM DIAGNOSIS. Correct the cause of trouble. Perform the Clear Memory Mode. < Ref. to OPERATION , Clear Memory Mode. > Read the DTC. < Ref. to OPERATION , Read Diagnostic Trouble Code (DTC). >	Is DTC displayed?	Repeat step 8 until DTC is not shown.	Finish the diagnosis.