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Inspection Mode I

DTC Description & trouble part Condition Number of driving cycles on the detecting condition
P0455 EVAP SYSTEM (CPC) LEAK DETECTED (LARGE LEAK)
  • [Coolant Temp.] 5 - 45 ° (41 - 113 °F)
  • [Intake Air Temperature]: 5 - 50 °C (41 - 122 °F)
 2
P0456 EVAP SYSTEM (CPC) LEAK DETECTED (VERY SMALL LEAK) 2
P04AE EVAP SYSTEM PURGE CONTROL VALVE "B" PERFORMANCE/STUCK OPEN 2
P1451 EVAP SYSTEM CLOG DETECTED (PIPE) 2
P2402 EVAP SYSTEM LEAK DETECTION PUMP CONTROL CIRCUIT HIGH 1
P2404 EVAP SYSTEM LEAK DETECTION PUMP SENSE CIRCUIT RANGE/PERFORMANCE 2
P2420 EVAP SYSTEM SWITCHING VALVE CONTROL CIRCUIT HIGH 1
WARNING: When performing inspection mode I on a public road, pay sufficient attention to the traffic condition and give the highest priority to safe driving.
CAUTION: Be careful of the state of the battery when performing the inspection mode I consecutively. Performing the inspection mode I consecutively without the engine running may cause a low battery voltage and battery discharge.
NOTE:
  • If it is necessary to perform inspection mode I consecutively, drive the vehicle under the following conditions to release accumulated evaporating gas. Performing the inspection mode I consecutively without starting the engine causes a large amount of evaporating gas to accumulate in the canister, which hinders an accurate diagnosis.
    • After engine is warmed up
    • Drive for 10 minutes or more at a speed of 48 km/h (30 MPH) or more (duration of drive can be an accumulation)
  • To obtain an accurate diagnostic result, perform the procedures according to the following points.
    • Do not refuel gas immediately before performing inspection mode I. There will be a large amount of evaporating gas immediately after refuel, which may cause a less accurate diagnostic performance.
    • Do not shake the vehicle while performing inspection mode I. Shaking the vehicle causes evaporating gas to increase inside the fuel tank, which may cause a less accurate diagnostic performance.
    • Do not perform any service operation including installation or removal of parts or connectors while performing inspection mode I. Performing service operation could affect on the functions of related parts, which may cause a less accurate diagnostic performance.
  • Perform MODE $08 when using a general scan tool.
  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. Prepare the Subaru Select Monitor kit. Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>General Description>PREPARATION TOOL .
  3. Prepare PC with Subaru Select Monitor installed.
  4. Connect the USB cable to the DST-i and the USB port on the personal computer (dedicated port for the Subaru Select Monitor).
    NOTE: The dedicated port for the Subaru Select Monitor means the USB port which was used to install the Subaru Select Monitor.
  5. Connect the diagnosis cable to DST-i.
  6. Connect the DST-i to the data link connector located in the lower portion of the instrument panel (on the driver's side).
    CAUTION: Do not connect the scan tools except for Subaru Select Monitor and general scan tool.
    G13866183Courtesy of SUBARU OF AMERICA, INC.
  7. Start the PC.
  8. Turn the ignition switch to ON (engine OFF) and run the "PC application for Subaru Select Monitor".
  9. On [Start] screen, select [Generic OBDII].
  10. On [Select System] screen, select [Evaporative System Leak Test].
  11. On [Evaporative System Leak Test] screen, select [Evaporative System Leak Test].
  12. On [Evaporative System Leak Test is running. Press Cancel to exit this function.] screen, click the [OK] button to perform evaporative system leak test.
  13. When [Conditions have been enabled to control this function. Turn the ignition switch off to terminate the test.] display appears, wait for 30 minutes without clicking the [OK] button.
    CAUTION: Do not leave the vehicle for an extended period of time after the test is complete. This may cause early deterioration of the battery or discharged battery.
    NOTE:
    • Clicking [OK] button brings [Evaporative System Leak Test] display back, although the test is continuing.
    • The Subaru Select Monitor screen does not change after the evaporative system leak test is complete or when the test is aborted by turning off the ignition switch.
    • If [Test conditions are not correct] screen is displayed, use the Subaru Select Monitor to check that the values of [Coolant Temp.] and [Intake Air Temp.] meet the criteria. If the conditions are satisfied, perform the inspection mode. Ref. to COMMON (diag)>CLEAR MEMORY .
  14. After 30 minutes passed from the start of step 13), click the [OK] button to return to the [Evaporative System Leak Test] display.
  15. Return to the [OBD System] screen, and select [OBD Mode test results].
  16. Check TID $C1 - $CA of MID $3C in [OBD Mode test results].
    NOTE: Perform MODE $06 and check when using a general scan tool.
    RESULT OF ON-BOARD MONITOR TEST

    Display Details Remarks
    $0000 is stored in all Val. During the evaporative system leak test, the test conditions were not met and the test was canceled. Once the test conditions are met, perform the test again.
    All Val. are stored with values and OK is set to all the results. Evaporative system leak test is completed correctly. While the ignition switch is ON, read the pending code using the Subaru Select Monitor.
    Some results were no good. The evaporative system leak test completed successfully but the results were faulty. While the ignition switch is ON, read the pending code using the Subaru Select Monitor.
  17. When the evaporative system leak test is completed correctly, read the pending code with the ignition switch turned to ON position. If the DTC is recorded, check the appropriate DTC. Ref. to COMMON (diag)>DIAGNOSTIC TROUBLE CODE (DTC) .
    NOTE:
    • Perform MODE $07 when using a general scan tool.
    • The pending code will be cleared by turning ignition switch to OFF.
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