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Home >> Lexus >> 2006 >> GS 430 >> Repair and Diagnosis >> Engine Performance >> Remove, Overhaul & Install >> Engine Control System (3UZ-FE) >> 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

Fig 1: Identifying Confirmation Driving Pattern
G04027026Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  1. Connect the intelligent tester to the CAN VIM. Then connect the CAN VIM to the DLC3.
  2. Start the engine and warm it up with all the accessories switched OFF until the ECT becomes stable.
  3. Run the engine at 2,500 to 3,000 RPM for about 3 minutes.

    HINT:

    Control the engine RPM so that the calculated catalyst temperature can be between 550 and 800°C (1,022 and 1,472°F). The calculated catalyst temperatures of bank 1 and bank 2 can be read by viewing CAT TEMP B1S1 and CAT TEMP B2S1 of the DATA LIST.

  4. Confirm that heated oxygen sensor (bank 1 sensor 1 (OX1A) and bank 2 sensor 1 (OX2A)) have waveforms that are around 0.5 V during feedback to the ECM. Then check the waveform of the heated oxygen sensor (bank 1 sensor 2 (OX1B) and bank 2 sensor 2 (OX2B)) for the same waveforms (0.5 V during feedback).
    Fig 2: Identifying Catalyst Temperature Graph
    G04027027Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    HINT:

    If there is a malfunction in the catalyst, the waveform of the heated oxygen sensor (sensor 2) (OX1B, OX2B) is almost the same as that of the heated oxygen sensor (sensor 1) (OX1A, OX2A), which is shown.