Confirmation Engine Racing Pattern

WARNING: This page is about a different car, the 2004 Lexus IS 300. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: Confirmation Engine Racing Pattern

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Connect the hand-held tester to the DLC3, or connect the probe of the oscilloscope between terminals OX1A, OX1B, OX2A, OX2B and E1 of ECM connectors
Start the engine and warm it up with all the accessories switched OFF until engine coolant temperature is stable
Race the engine at 2,500-3,000 RPM for about 3 min.
After confirming that the waveform of the heated oxygen sensor (bank 1,2 sensor 1 (OX1A, OX2A)), oscillate around .5V during feedback to the ECM, check the waveform of the heated oxygen sensor (bank 1,2 sensor 2 (OX1B, OX2B)).

HINT:

If there is a malfunction in the system, the waveform of the heated oxygen sensor (bank 1,2 sensor 2 (OX1B, OX2B0)) is almost the same as that of the heated oxygen sensor (bank 1, 2 sensor 1 (OX1A, OX2A)) on the left.

There are some cases were, even though a malfunction exists, the MIL may either light up or not light up.

Fig 2: Identifying OX Signal Waveform