2019 Subaru Crosstrek Base, Automatic CVT TransFACTORY OEM SERVICE PROCEDURE

Inspection Mode V

DTC Item Condition Number of driving cycles on the detecting condition
P0420 CATALYST SYSTEM EFFICIENCY BELOW THRESHOLD BANK 1 - 2
WARNING: When performing inspection mode V on a public road, pay sufficient attention to the traffic condition and give the highest priority to safe driving.

Diagnostic procedure:Β 

  1. Drive according to the drive pattern described below.
    G13238582Courtesy of SUBARU OF AMERICA, INC.
    NOTE:
    • The condition of acceleration or constant driving can be changed according to different traffic conditions.
    • If diagnostic values have not been input after driving, repeat the cycle from step (C) without stopping the engine.
  2. Read the temporary code using the Subaru Select Monitor or general scan tool. Refer to COMMON (DIAG)>DIAGNOSTIC TROUBLE CODE (DTC) .
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.