Conditioning For Sensor Testing

Fig 1: Engine Speed Graph

(a) Connect the Techstream to the DLC3.
(b) Start the engine and warm it up with all the accessories switched OFF until the engine coolant temperature stabilizes.
(c) Run the engine at an engine speed of between 2500 rpm and 3000 rpm for at least 3 minutes.
(d) While running the engine at 3000 rpm for 2 seconds and 2000 rpm for 2 seconds, check the waveforms of the HO2 sensors using the Techstream.
HINT:

Control the engine RPM so that the calculated catalyst temperature can be between 500 and 800°C (932 and 1472°F). The calculated catalyst temperatures of bank 1 and bank 2 can be read by viewing Catalyst Temp (B1 S1) and Catalyst Temp (B2 S1) of the Data List.
(e) 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: Catalyst Temperature Graph
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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.