It is performed by measuring and comparing the response periods of oxygen sensors.
There are two types of possible faults with inlet oxygen sensors:
- mechanical failure of one of the electrical components (breakage, wire breakage), which is classified as an electrical fault;
- chemical failure of the component, which leads to an increase in the response time of the sensor and, consequently, to an increase in its response period.
After the test conditions are met, the obtained sensor periods are averaged (discarding parasitic effects) and compared with the average threshold period "OVO".
Test conditions
Upstream oxygen sensor diagnostics can only be performed after the engine has been running for 15 minutes if the pre-ignition conditions are met and are being fulfilled.
- no electrical faults;
- programming and cylinder recognition completed;
- since the ignition was turned on, the oxygen sensor diagnostics have not been performed;
- no misfires detected;
- coolant temperature above 75°C;
- the average engine crankshaft speed is within the range of 1824-4000 min' for the F4P engine and 1632-4000 min' for the K4M engine;
- the pressure is within 328-750 mbar;
- the car moves at a speed of 63-130 km/h,
Troubleshooting
The diagnostics are performed by the customer during the trip in accordance with the conditions described above, with the purge prohibition and the canister emptying. This test is performed for at least 40 s. The ECU issues the indication "oxygen sensor diagnostics: in progress".
The test duration cannot exceed 52 s without exiting the loop.
Caution! At the end of this test, do not turn off the ignition under any circumstances before reading the result on the diagnostic tool. Turning off the ignition will result in incorrect interpretation of the results.
Confirmation of repair
Enter the command "Oxygen sensor diagnostics using the on-board diagnostics system is in progress": "ACTIVE".
Oxygen sensor diagnostics using the on-board diagnostics system has been completed: "ACTIVE".
Oxygen sensor malfunction: "INACTIVE".
Oxygen sensor repair confirmation: "YES".
If the diagnostic tool displays Oxygen Sensor On-Board Diagnostics: "completed. ACTIVE" or "Oxygen Sensor Repair Confirmed. 1DEF", the test cycle has not been performed correctly. In this case, repeat the test cycle strictly observing the diagnostic conditions.
If the diagnostic tool displays the message "Catalytic Converter Malfunction ACTIVE" or "Oxygen Sensor Repair Confirmation 2DEF" after the test, refer to the diagnostic method corresponding to the malfunction.