DTC Detection Logic

To judge malfunctions, this diagnosis measures response time of the A/F signal computed by ECM from the A/F sensor 1 signal. The time is compensated by engine operating (speed and load), fuel feedback control constant, and the A/F sensor 1 temperature index. Judgment is based on whether the compensated time (the A/F signal cycling time index) is inordinately long or not.

DTC No.	Trouble diagnosis content	DTC detecting condition	Possible Cause
P014C	Air fuel ratio (A/F) sensor 1 (bank 1) circuit slow response	The response time of a A/F sensor 1 signal delays more than the specified time computed by ECM.	Harness or connectors (The A/F sensor 1 circuit is open or shorted.) A/F sensor 1
P014D
P015A	Air fuel ratio (A/F) sensor 1 (bank 1) circuit delayed response
P015B