2022 Subaru Legacy BaseFACTORY OEM SERVICE PROCEDURE

Basic Diagnostic Procedure: Procedure

  1. PERFORM CUSTOMER INTERVIEW  .

    Ask the customer when and how the trouble occurred using the interview check list. Ref. to Front Relay Control Module (Diagnostics)>Check List for Interview .

    Did you interview the customer?

    Yes:  Go to  2 .

    No:  Perform the interview, and Go to  2 .

  2. BASIC INSPECTION  .

    Perform basic inspection. Ref. to FRONT RELAY CONTROL MODULE (DIAGNOSTICS)>General Description>INSPECTION .

    Is the check result OK?

    Yes:  Go to  3 .

    No:  Repair the faulty part found in basic inspection, and Go to  3 .

  3. CHECK SUBARU SELECT MONITOR COMMUNICATION  .
    1. Turn the ignition switch to OFF.
    2. Connect the Subaru Select Monitor to data link connector. Ref. to COMMON (DIAG)>DATA LINK CONNECTOR .
    3. Turn the ignition switch to ON and run the Subaru Select Monitor.
    4. Select [Front Relay Control Module].
      NOTE:

      For detailed operation procedures, refer to "Help" of application. 

      Is communication possible?

      Yes:  Go to  4 .

      No:  Check the communication circuit. Ref. to Front Relay Control Module (Diagnostics)>Diagnostic Procedure for Subaru Select Monitor Communication .

  4. CHECK DTC  .
    1. Read the DTC of [Front Relay Control Module] using the Subaru Select Monitor. Ref. to Front Relay Control Module (Diagnostics)>Diagnostic Trouble Code (DTC) .
    2. Record all DTCs and time stamp.
      NOTE:

      For time stamp, refer to "LAN SYSTEM". Ref. to  LAN SYSTEM (DIAGNOSTICS)>GENERAL DESCRIPTION>CAUTION>TIME STAMP  . 

      Are any DTCs displayed? (Current malfunction)

      Yes:  Record the DTC, time stamp and freeze frame data, and Go to  5 .

      No:  Perform diagnosis according to the procedures in the diagnostics with phenomenon. Ref. to Diagnostics With Phenomenon .

  5. PERFORM DIAGNOSIS  .
    1. Perform the diagnosis according to the displayed DTC. Ref. to FRONT RELAY CONTROL MODULE (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST .
    2. Repair or replace the cause of trouble.
    3. Using the Subaru Select Monitor, perform the clear memory of [Front Relay Control Module]. Ref. to COMMON (DIAG)>CLEAR MEMORY .
    4. Execute the inspection mode. Ref. to Front Relay Control Module (Diagnostics)>Inspection Mode .
    5. Read the DTC of [Front Relay Control Module] using the Subaru Select Monitor. Ref. to Front Relay Control Module (Diagnostics)>Diagnostic Trouble Code (DTC) .

      Are any DTCs displayed? (Current malfunction)

      Yes:  Repeat step  5 until DTC is not shown.

      No:  Finish the diagnosis.

Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.