Sensor voltage detection monitor

Under the air-fuel ratio feedback control, if the A/F sensor voltage output indicates rich or lean for a certain period of time, the ECM determines that there is a malfunction in the A/F sensor. The ECM illuminates the MIL and sets a DTC. Example:

If the A/F sensor voltage output is less than 2.8 V (very rich condition) for 10 seconds, despite the rear HO2 sensor voltage output being less than 0.60 V, the ECM sets DTC P2196. Alternatively, if the A/F sensor voltage output is more than 3.8 V (very lean condition) for 10 seconds, despite the rear HO2 sensor voltage output being 0.15 V or more, DTC P2195 is set.

Do It Yourself Car Diagnosis

Do It Yourself Car Diagnosis

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