Bank 1: The bank of cylinders that contains cylinder number 1.
Sensor 1: The oxygen sensor that is closest to the engine.
The oxygen sensor is a sensor that measures the amount of oxygen in the exhaust gas. The heater circuit is a circuit that heats the oxygen sensor so that it can reach its operating temperature quickly. If the heater circuit is not working properly, the oxygen sensor will not be able to reach its operating temperature and will not be able to provide accurate readings to the engine control unit (ECU).
The ECU uses the oxygen sensor readings to adjust the air/fuel mixture. If the oxygen sensor readings are not accurate, the air/fuel mixture will not be correct and this can cause a number of problems, including:
* Reduced fuel economy
* Increased emissions
* Poor engine performance
* Engine damage
If you see the P0135 code, you should have the oxygen sensor and heater circuit checked as soon as possible.
