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Home >> Subaru >> 2019 >> Ascent Base >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System (Diagnostics - Introduction) >> Inspection Mode >> Procedure >> Inspection Mode U
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Inspection Mode U

DTC Item Condition Number of driving cycles on the detecting condition
P0401 EGR ABNORMAL (EGR AMOUNT TOO SMALL) - 2
P0402 EGR "A" FLOW EXCESSIVE DETECTED - 2
WARNING: When performing inspection mode U on a public road, pay sufficient attention to the traffic condition and give the highest priority to safe driving.
  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 (DIAG)>CLEAR MEMORY .
  3. Drive according to the drive pattern described below.
    G13202320Courtesy of SUBARU OF AMERICA, INC.
  4. Read the temporary code using the Subaru Select Monitor or general scan tool. Ref. to COMMON (DIAG)>DIAGNOSTIC TROUBLE CODE (DTC) .