On-Vehicle Inspection

ON-VEHICLE INSPECTION

1. INSPECT AIR FUEL RATIO SENSOR







a. Measure the voltage of the ECM connectors.

HINT: Voltage of the engine ECM is kept constant regardless of the voltage of the A/F sensor.

NOTE: Connect test leads to the connector's backside. The connectors should not be disconnected from the ECM.

b. Connect the intelligent tester to the DLC3.
c. Select "DATA MONITOR". Then select "A/FS B1 S1", "A/FS B2 S1" and "O2S B1 S2" to display the monitors.
d. Warm up the A/F sensor with the engine speed at 2,500 rpm for approximately 2 minutes.




e. Maintain engine speed at 2,500 rpm and confirm that the displays of "A/FS B1 S1" and "A/FS B2 S1" are as shown in the illustration.

HINT:
- The illustration may differ slightly from the display on the intelligent tester.
- Only the intelligent tester displays the waveform of A/F sensor.

f. Confirm that the display of "O2S B1 S2" changes between 0 to 1 V with the engine speed at 2,500 rpm.