Diagnostic Method 1

Detect the malfunction by checking "Cumulative value of time when λ changes from lean → rich" in comparison to "Time during which diagnosis is in progress".

Fig 1: Cumulative Time Waveform

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Judge as NG when the following conditions are established.

JUDGMENT VALUE

Malfunction Criteria	Threshold Value	DTC
(Cumulative value of time when λ changes from lean → rich)/(Time during which diagnosis is in progress)	< 0.35	P014C
	> 0.65	P014D

Time Needed for Diagnosis: 70000 ms

Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cycles.