Details On DTCs

WARNING: This page is about a different variant/trim than selected.

P0421-00: (PCM - VIN Y) DETECTION CONDITION AND POSSIBLE CAUSE

System malfunction location	Catalytic converter system
Detection condition	Determination conditions	The PCM detects that the HO2S output fluctuates from lean to rich in a short amount of time at specified times continuously after recovery from fuel cut control.
	Preconditions	Catalytic converter (WU-TWC) is activated sufficiently. A/F sensor is activated sufficiently. HO2S is activated sufficiently. The following DTCs are not detected: Misfire: P0300:00, P0301:00, P0302:00, P0303:00 and P0304:00 Fuel injection correction: P0171:00 and P0172:00 A/F sensor: P0130:00, P0131:00, P0132:00, P0133:00, P0134:00, P064D:00, P2237:00, P2243:00 and P2251:00 HO2S: P0137:00, P0138:00, P013A:00 and P0140:00 A/F sensor heater: P0031:00 and P0032:00 HO2S heater: P0037:00 and P0038:00
	Malfunction determination period	Not applicable
	Drive cycle	2
	Self test type	CMDTC self test
	Sensor used	A/F sensor, HO2S
Fail-safe	Not applicable
Vehicle status when DTCs are output	Not applicable
Possible cause	HO2S malfunction HO2S incorrect installation A/F sensor malfunction A/F sensor incorrect installation Exhaust gas leakage from exhaust system A/F sensor deterioration Catalytic converter (WU-TWC) malfunction (deterioration) PCM malfunction