An indicator of the condition of the catalytic converter is its oxygen capacity. As the catalytic converter ages, its oxygen capacity decreases as well as its ability to neutralize exhaust gases.
Conditions for starting diagnostics
Catalytic converter diagnostics can only be performed after the engine has been running for 17 minutes, if the conditions preceding turning on the ignition are met and maintained.
- no electrical faults;
- cylinder recognition completed;
- no misfires detected;
- after turning on the ignition, diagnostics of the catalytic converter was not performed;
- programming done;
- the main and dual circuits for regulating the mixture composition are activated based on signals from oxygen sensors;
- coolant temperature above 75°C;
- The car moves at a speed of 63 to 130 km/h;
- the pressure is within 430-650 mbar;
- the engine crankshaft speed read from the diagnostic device is within the range of 1824-3712 min⁻¹ for the F4P engine and 1824-4000 min⁻¹ for the K4M engine.
Troubleshooting
Diagnostics are performed with the vehicle moving steadily in 5th gear at a speed of 70 km/h. If the diagnostic start conditions are met, the mixture enrichment process is delayed in time, which results in the flow of oxygen portions into the catalytic converter. If the catalytic converter is operational, it absorbs oxygen and the voltage value of the downstream oxygen sensor signal remains at an average level. If the catalyst has exhausted its resource, oxygen is not absorbed and the oxygen sensor begins to work intermittently. The oxygen sensor signal voltage will fluctuate. The on-board diagnostics system warning lamp will light after three trips. The test duration cannot exceed 52 s without exiting the cycle.
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 "catalytic converter diagnostics in progress using the on-board diagnostics system": "ACTIVE".
Information is located on the website RENAULTBOOK
"On-Board Diagnostics Catalytic Converter Diagnostics: Completed": "ACTIVE".
"Catalytic converter malfunction": "NOT ACTIVE".
"Catalytic Converter Repair Confirmation": "YES".
If the diagnostic tool displays "On-Board Diagnostics: Complete. ACTIVE" or "Catalytic Converter Repair Confirmed. 1DEF", the test cycle has not been performed correctly. In this case, repeat the test cycle while strictly observing the diagnostic conditions.
If the diagnostic tool displays the message "Catalytic Converter Malfunction ACTIVE" or "Catalytic Converter Repair Confirmation 2DEF" after the test, refer to the diagnostic method corresponding to the malfunction.