Toyota Corolla (E120): Diagnosis circuit

Wiring diagram

Circuit description

Other materials:

Cooling
Preparation Recomended tools Equipment Coolant ...

Initialization
1. Reset memory Caution: perform the reset memory (at initialization) when replacing the automatic transaxle assy, engine assy or ecm. Notice: hand–held tester only Turn the ignition switch off.  connect the hand–held tester to the dlc3.  turn the ignition switch to th ...

Circuit description
The ecm compares the two waveforms of the heated oxygen sensors located before and after the catalyst to determine whether or not the catalyst performance has deteriorated. Air–fuel ratio feedback compensation keeps the waveform of the heated oxygen sensor in front of the catalyst alterna ...