2018 Subaru WRX BaseFACTORY OEM SERVICE PROCEDURE

Inspection Mode 1

WARNING: This page is about a different car, the 2022 Subaru WRX. However, it is still accessible from the selected car via links, so may be relevant.
DTC Description & trouble part Note
B1A00 FRONT RELAY CONTROL MODULE NON-VOLATILE MEMORY -
B1A01 FRONT RELAY CONTROL MODULE BATTERY (CONTROL) POWER SUPPLY -

Diagnostic procedure:

  1. Using the Subaru Select Monitor, perform the clear memory of [Front Relay Control Module]. Ref. to COMMON (DIAGNOSTICS)>CLEAR MEMORY
  2. Using the Subaru Select Monitor, read the DTC of [Front Relay Control Module] to check that there is no DTC displayed. Ref. to FRONT RELAY CONTROL MODULE (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC)Β 
    NOTE:

    If the DTC is displayed on the screen, the trouble is still present. Perform the diagnosis for the displayed DTCs. After solving the DTC, repeat from step Β Β 1Β .Β 

  3. Disconnect and reconnect the battery, and then wait for one minute or more.
  4. Using the Subaru Select Monitor, read the DTC of [Front Relay Control Module] to check that there is no DTC displayed. Ref. to FRONT RELAY CONTROL MODULE (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC)Β 
    NOTE:

    If the DTC is displayed on the screen, the trouble is still present. Perform the diagnosis for the displayed DTCs.Β 

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:

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

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