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Inspection Mode Ab

DTC Description & trouble part Condition Number of driving cycles on the detecting condition
P0039 TURBOCHARGER/SUPERCHARGER BYPASS VALVE "A" CONTROL CIRCUIT RANGE/PERFORMANCE - 2
P0234 TURBOCHARGER/SUPERCHARGER "A" OVERBOOST CONDITION - 2
P0299 TURBOCHARGER/SUPERCHARGER "A" UNDERBOOST CONDITION - 2
P226B TURBOCHARGER/SUPERCHARGER BOOST PRESSURE TOO HIGH - MECHANICAL - 1
WARNING: When performing inspection mode AB 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.
  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, clear the memory of [Engine Control System]. Ref. to COMMON (DIAGNOSTICS)>CLEAR MEMORY .
  3. Drive according to the drive pattern described below.
    G16390330Courtesy of SUBARU OF AMERICA, INC.
    (1) 0 km/h (0 MPH)
    (2) 30 km/h (18.6 MPH)
    (3) 80 km/h (50 MPH)
    (A) Accelerate and drive at a constant speed of 30 km/h (18.6 MPH) with the gear in 3rd speed. (Keep the gear in 3rd speed of the manual mode)
    (B) Accelerate with fully open throttle to 80 km/h (50 MPH) without shifting.
    (C) Decrease the speed to 30 km/h (18.6 MPH) while holding the gear in 3rd speed.
    (D) Slow down and stop the vehicle.
    (E) Vehicle speed
    (F) Driving duration
  4. Read the pending code using the Subaru Select Monitor or general scan tool. Ref. to COMMON (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .