PID/DATA Monitor Inspection (A/F Sensor)

WARNING: This page is about a different car, the 2017 Mazda 3. However, it is still accessible from the selected car via links, so may be relevant.

Connect the M-MDS to the DLC-2.
Start the engine and warm it up completely.
Access the following PIDs using the M-MDS. (See ON-BOARD DIAGNOSTIC TEST .)
- VSS (Vehicle speed)
- RPM (Engine speed)
- O2S11 (A/F sensor output current)
Drive the vehicle and decelerate the engine speed by releasing the accelerator pedal fully when the engine speed is 3, 000 rpm or more.
Verify that the A/F sensor output current (PID: O2S11) is 0.25 m A or more while decelerating as shown in the figure.

Fig 1: A/F Sensor Output Current Graph
Courtesy of MAZDA MOTORS CORP.
- If not as verified, replace the A/F sensor. (See AIR FUEL RATIO (A/F) SENSOR REMOVAL/INSTALLATION .)