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Inspection Mode AO

DTC Description and trouble part Condition Number of driving cycles on the detecting condition
P0420 CATALYST SYSTEM EFFICIENCY BELOW THRESHOLD BANK 1 - 2
WARNING: When performing inspection mode AO on a public road, pay sufficient attention to the traffic condition and give the highest priority to safe driving.
NOTE:
  • Perform the inspection mode after warming up the engine except that the engine coolant temperature at engine start is specified  .
  • Even if switched to the hybrid battery save mode under the following conditions, the engine may not start  .
  • Power from HV battery is low and reduction in SOC is slight  .
  • SOC is recovering due to regeneration, etc  .
  1. Check that the battery voltage is 12 V or more and fuel remains approx. half [20 - 40 L (5.3 - 10.6 US gal, 4.4 - 8.8 Imp gal)].
  2. Using the Subaru Select Monitor, perform the clear memory of [Engine]. Ref. to COMMON (DIAG)>CLEAR MEMORY .
  3. Drive according to the drive pattern described below.
    G13941775Courtesy 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 diagnosis 3 without stopping the engine  .
  4. Read the temporary code using the Subaru Select Monitor or general scan tool. Ref. to COMMON (DIAG)>DIAGNOSTIC TROUBLE CODE (DTC) .