Fault code description - three-way catalytic converter effectiveness too low - AD07.61-P-4000-16M

1	Fault code	P200B The efficiency of the right catalytic converter is insufficient (P0422)
	(Fault code according to OBD)	P20A3 The efficiency of the left catalytic converter is insufficient (P0432)
2	Fault storage	After expiry of test duration and fault
	Actuation of engine diagnosis indicator lamp (EURO4) or CHECK ENGINE (MIL)	Following two successive driving cycles with faults
3	Checking frequency	Once per driving cycle
4	Checked signal or status	Comparison of amplitude of the O2 -sensor signal downstream of TWC with the characteristic map value
5	Fault setting conditions
	Limit value	The amplitude of the O2 sensor signal downstream of the TWC must not be greater than 40 % more than the respective characteristic map value
	Checking duration	Approx. 30 seconds
6	Check prerequisites	Engine speed approx. 1200 to 1900 RPM Load approx. 22 to 55% Catalytic converter temperature 480°C to 680°C Lambda control enabled No fault in O2 sensors (signal, heater, aging) No high loading of the activated charcoal canister No misfiring No fault in secondary air injection No fault in leaktightness of purge system
7		The three-way catalytic converter is evaluated on its ability to store oxygen. The oxygen stored during a lean-mixed phase is either completely or partially consumed during a rich-mixed phase. The storage capacity and thus also the HC conversion are reduced through aging. If the fault codes for the TWC and for the O2 sensors are issued identically, the O2 sensors should be replaced first. If then a TWC fault is no longer detected, and if the effect of the three-way catalytic converter has been slightly reduced, it does not need to be replaced yet.