Confirmation Driving Pattern

Fig 1: Identifying Confirmation Driving Pattern

If using the intelligent tester: Connect the intelligent tester to the DLC3.
If not using the intelligent tester: Connect oscilloscope tester probes to terminals OX1A (front Heated Oxygen [HO2] sensor: Sensor 1), OX1B (rear HO2 sensor: Sensor 2) and E1 of the ECM connector.
Start the engine.
Warm up the engine with all the accessories switched OFF until the engine coolant temperature stabilizes.
Run the engine at an engine speed between 2,500 rpm and 3,000 rpm for approximately 3 minutes.
Check that the waveform of the OX1A (rear HO2 sensor) signal.

Fig 2: Identifying Front HO2 Sensor Signal Waveform
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HINT:

If there is still a malfunction in the system, the waveform of OX1B may become similar to the OX1A waveform shown in the diagram above.