Toyota Corolla (E120): Oxygen sensor circuit malfunction

Inspection procedure

Circuit description

Other materials:

Circuit description
When a misfire occurs in the engine, hydrocarbons (hc) enter the exhaust in high concentrations. If this hc concentration is high enough, there could be an increase in exhaust emissions levels. High concentrations of hc passing through the catalyst also cause to temperature of the catalyst to ...

Exhaust gas precautions
Harmful substance to the human body is included in exhaust gases if inhaled. WARNING Exhaust gases include harmful carbon monoxide (CO), which is colorless and odorless. Observe the following precautions. Failure to do so may cause exhaust gases enter the vehicle and may lead to an accident caused ...

Circuit description
In the diagram below, when the engine is cranked, current flows from terminal st2 of the ignition switch to the starter relay coil and also current flows to terminal sta of the ecm (sta signal). When the sta signal and ne signal are input to the ecm, tr is turned on, current flows to the c ...