2021 Subaru WRX STIFACTORY OEM SERVICE PROCEDURE

Activation Of Malfunction Indicator Light

  1. When the ignition switch is turned to ON (engine OFF), the malfunction indicator light (A) in the combination meter illuminates.
    NOTE: If the malfunction indicator light does not illuminate, perform diagnostics of the malfunction indicator light circuit or the combination meter circuit.. Refer to ENGINE (DIAGNOSTICS) (STI)>MALFUNCTION INDICATOR LIGHT>MALFUNCTION INDICATOR LIGHT DOES NOT COME ONΒ .
    G10265791Courtesy of SUBARU OF AMERICA, INC.
  2. After starting the engine, the malfunction indicator light goes out. If it does not go off, any of the engine and emission control system has malfunction.
    G13650076Courtesy of SUBARU OF AMERICA, INC.
  3. If the diagnostic system detects a misfire which could damage the catalyst, the malfunction indicator light will blink at a cycle of 1 Hz.
    G13650077Courtesy of SUBARU OF AMERICA, INC.
  4. Turn the ignition switch to OFF and install the delivery mode fuse (A).
    CAUTION: Do not use any fuses that are installed on the vehicle.
    G10265783Courtesy of SUBARU OF AMERICA, INC.
    1. When the ignition switch is turned to ON (engine OFF), the malfunction indicator light illuminates.
    2. After the engine starts, malfunction indicator light blinks in a cycle of 0.5 Hz. (During diagnosis)
    3. Malfunction indicator light blinks at a cycle of 3 Hz after diagnosis if there is no trouble. Malfunction indicator light illuminates if faulty.
    G13650079Courtesy of SUBARU OF AMERICA, INC.
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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.