Monitor Description
A rich air fuel mixture causes a low air fuel ratio sensor (sensor 2) current, and a lean air fuel mixture causes a high air fuel ratio sensor (sensor 2) current. Therefore, the sensor output becomes low during acceleration, and it becomes high during deceleration with the throttle valve fully closed. The ECM monitors the air fuel ratio sensor (sensor 2) current during fuel-cut and detects any abnormal current values.
If the air fuel ratio sensor (sensor 2) output is 33.13 mA or more for 0.5 seconds or more of cumulative time, the ECM interprets this as a malfunction of the air fuel ratio sensor (sensor 2) and stores DTC P2270-19 (stuck on high side). If the air fuel ratio sensor (sensor 2) output is less than 7.5 mA for 0.5 seconds or more of cumulative time, the ECM stores DTC P2271-18 (stuck on low side).
