What are the four wires of the oxygen sensor?

Two white lines are heating lines; One black is the signal line; Grey signal ground wire. The four wire of that oxygen sensor are two white wires and an electric heat wire respectively; One black is the signal line; A gray signal grounding wire and a heating wire are used to make the oxygen sensor work faster. Automobile oxygen sensor is the key feedback sensor in the control system of EFI engine, and it is the key component to control automobile exhaust emission, reduce automobile pollution to the environment and improve the fuel combustion quality of automobile engine.