Operation CHARM: Car repair manuals for everyone.

Air Fuel Ratio (A/F) Sensor Inspection




AIR FUEL RATIO (A/F) SENSOR INSPECTION [L5]

A/F Sensor Current Inspection

1. Warm up the engine to normal operating temperature.

2. Using the M-MDS, monitor the following:

- Vehicle speed (PID: VSS)
- Engine speed (PID: RPM)
- A/F sensor current (PID: O2S11)

3. Drive the vehicle and decelerate the engine speed by releasing the accelerator pedal fully when the engine speed is 3,000 rpm or more.

4. Verify that the A/F sensor current (PID: O2S11) is 0.25 mA or more while decelerating as shown in the figure.






- If not within the specification, replace the A/F sensor. Air Fuel Ratio (A/F) Sensor Removal/Installation

A/F Sensor Heater Resistance Inspection

1. Disconnect the A/F sensor connector.

2. Measure the resistance between A/F sensor terminals A and E.






- If not as specification, replace the A/F sensor. Air Fuel Ratio (A/F) Sensor Removal/Installation

A/F sensor heater resistance
- 1-10 ohms