P0051 P0051 code definition HO2S Heater Control Circuit Low (Bank 2 Sensor 1) What the P0051 code means This code is set when the car’s computer, or Engine Control Module (ECM), detects low system voltage in the heater control circuit....
Oxygen sensors do not work until they reach a certain temperature. The electric heating element helps the sensor come up to temperature faster so that the engine can go into closed loop operation more quickly. P0051 says that there is...
