Basic Diagnostic Procedure: Procedure

CAUTION:

Subaru Select Monitor is required for reading DTC, performing diagnosis, reading current data, customizing and active test (compulsory drive).
Remove foreign matter (dust, water, oil, etc.) from each control module connector during removal and installation.
For model with immobilizer or model with keyless access, registration of immobilizer may be needed after the replacement of controller 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 Refer to CHECK LIST FOR INTERVIEW .

Step	Check	Yes	No
1 CHECK PRE-INSPECTION. Ask the customer when and how the trouble occurred using the interview check list. Refer to CHECK LIST FOR INTERVIEW .	Did you interview the customer?	Go to step 2 .	Interview the customer.
2 BASIC INSPECTION. Check components which might affect CAN communication problem. Refer to INSPECTION .	Is the component that might affect CAN communication problem normal?	Go to step 3 .	Repair or replace each component.
3 CHECK DTC. Start the engine and read all DTCs. NOTE: When the engine does not start, perform the diagnosis for the engine start malfunction. Refer to DIAGNOSTICS FOR ENGINE STARTING FAILURE (H4DO). Refer to DIAGNOSTICS FOR ENGINE STARTING FAILURE (H6DO). If the communication function of the Subaru Select Monitor cannot be executed properly, check the communication circuit. Refer to COMMUNICATION FOR INITIALIZING IMPOSSIBLE . Record all DTCs and freeze frame data.	Is DTC regarding CAN communication displayed on Subaru Select Monitor?	Go to step 5 .	Go to step 4 .
4 PERFORM GENERAL DIAGNOSTICS. Inspect using the "General Diagnostic Table". Refer to GENERAL DIAGNOSTIC TABLE .	Is result of inspection OK?	LAN system is normal.	Go to step 5 .
5 PERFORM DIAGNOSIS. Correct the cause of trouble. Perform the Clear Memory Mode. Refer to OPERATION . Read the DTC. Refer to OPERATION .	Is DTC displayed on Subaru Select Monitor?	Repeat step 5 until DTC is not shown.	Finish the diagnosis.