Conditioning For Sensor Testing

Fig 1: Driving Pattern Of Engine Speed And Time

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Connect Techstream to the DLC3.
2. Put the engine in inspection mode (see SFI SYSTEM  ).
3. Start the engine and warm it up with all the accessories switched OFF until the engine coolant temperature becomes stable.
4. Run the engine at 2,500 rpm for approximately 3 minutes.
5. Run the engine at 2,500 rpm for 2 seconds and then 1,500 rpm for 2 seconds.
6. Check the waveform of the oxygen sensor (sensor 2).

HINT:

If output of the A/F sensor or the heated oxygen sensor does not fluctuate or has noise, the sensor may be malfunctioning.

If voltage output of both sensors remain at LEAN or RICH, the air-fuel ratio may be extremely LEAN or RICH. In such a case, perform the following Control the Injection Volume for A/F Sensor operation in Active Test using Techstream. If the catalyst has deteriorated, the voltage output of the heated oxygen sensor fluctuates up and down widely even under normal driving ("active air-fuel ratio control" is not performed).

Fig 2: Voltage Output Waveform Graph

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002