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Home >> Lexus >> 2011 >> IS 350 Base, AWD >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System (Diagnostic Codes (P0171-P060A)) >> SFI System >> DTC P0420: Catalyst System Efficiency Below Threshold (Bank 1); DTC P0430: Catalyst System Efficiency Below Threshold (Bank 2) >> Confirmation Driving Pattern
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Confirmation Driving Pattern

HINT: 

Performing this confirmation driving pattern will activate the catalyst monitor. This is very useful for verifying the completion of a repair.

Fig 1: Identifying Confirmation Driving Pattern
GTY349430Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  1. Connect the Techstream to the DLC3.
  2. Turn the engine switch on (IG).
  3. Turn the Techstream on.
  4. Clear DTCs (even if no DTCs are stored, perform the clear DTC procedure). Refer to DTC CHECK / CLEAR .
  5. Turn the engine switch off and wait for at least 30 seconds.
  6. Turn the engine switch on (IG) and turn the Techstream on.
  7. Enter the following menus: Powertrain / Engine / Monitor / Current Monitor.
  8. Check that Catalyst Efficiency / Current is Incomplete.
  9. Start the engine and warm it up until the engine coolant temperature is 75°C (167°F) or more [A].
  10. Drive the vehicle at approximately 37 mph (60 km/h) for 10 minutes or more [B].

    HINT: 

    • Drive the vehicle while keeping the engine load as constant as possible.
    • The monitor item will change to Complete as the catalyst efficiency monitor operates [C].
  11. Enter the following menus: Powertrain / Engine / Trouble Codes.
  12. Check if any DTCs (pending DTCs) are stored.

    HINT: 

    If the monitor does not change to Complete, and no pending DTCs are stored, perform the following procedure.

  13. Drive the vehicle at a speed between 47 and 63 mph (75 and 100 km/h) for 10 minutes or more [D].
    WARNING:

    When performing the confirmation driving pattern, obey all speed limits and traffic laws.

    HINT: 

    • Drive the vehicle while keeping the engine load as constant as possible.
    • The monitor item will change to Complete as the catalyst efficiency monitor operates [E].
  14. Enter the following menus: Powertrain / Engine / Trouble Codes.
  15. Check if any DTCs (pending DTCs) are stored.