Circuit Description

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

Three-Way Catalyst (TWC) system is used to control emissions. PCM uses signal from Heated Oxygen Sensor (HO2S) behind TWC to read efficiency of TWC. PCM will set DTC P0140 if TWC oxygen storage capacity is less than a predetermined threshold.

Conditions required to set DTC are:

No ECT, IAT, MAF, MAP or TP sensor DTCs set.
No EVAP system DTC set.
No fuel injector circuit, fuel trim, misfire or transaxle DTCs set.
Closed loop commanded air/fuel ratio is 14.5-14.8:1.
Engine run time greater than 200 seconds.
HO2S 2 voltage stays 0.425-0.474 volt for 100 seconds.