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Home >> Toyota >> 2011 >> Prius >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (Diagnostic Codes) >> SFI System >> DTC P0420: Catalyst System Efficiency Below Threshold (Bank 1) >> Confirmation Driving Pattern
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Confirmation Driving Pattern

HINT: 

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

Fig 1: Identifying Power Switch / Scantool Operation Graph
GTY225301Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  1. Connect the Techstream to the DLC3.
  2. Turn the power switch on (IG).
  3. Turn the Techstream on.
  4. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
  5. Turn the power switch off.
  6. Turn the power switch on (IG) and turn the Techstream on.
  7. Enter the following menus: Powertrain / Engine and ECT / Monitor.
  8. Check that Catalyst Efficiency / Status2 is Incomplete.
  9. Put the engine in inspection mode. Refer to INSPECTION MODE PROCEDURE .
  10. Start the engine and warm it up (until the engine coolant temperature is 75°C (167°F) or higher) [A].
  11. Drive the vehicle at between 47 and 75 mph (75 and 120 km/h) for at least 10 minutes or more [B].
  12. Those items will change to Complete after completing the driving pattern.
  13. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes / Pending.
  14. Check if any DTCs (pending DTCs) are set.

HINT: 

If Catalyst does not change to Complete, and no pending DTCs are stored, extend the driving time.