An ignition voltage circuit with an in-line fuse supplies the voltage needed for the heater to function. That’s why they rely on a heating element in order for them to get up to operating temperature more quickly. Oxygen sensors need to reach a certain temperature to make really accurate oxygen level readings. The PCM also takes this information into account to finely tune the appropriate air-fuel mixture and calculate fuel delivery and ignition timing. The PCM uses the data from the oxygen sensors to measure the oxygen content in the exhaust. Oxygen sensors are typically installed in the exhaust and/or downstream from the manifold in the exhaust pipe. Zirconium is an electrically conductive material that’s capable of generating a small voltage in the presence of oxygen. Many oxygen sensors contain a Zirconium dioxide sensing element encased in a protective steel housing.
Consult the appropriate repair manual or repair database for the exact code definition. Note: The definition of code P0054 may be different depending on the vehicle manufacturer. If you have a Ford (especially a Ford Fiesta), Chevrolet, or GMC, your vehicle’s onboard diagnostics may register code P0054, and you must have the issue checked by a technician as soon as possible. The “Bank 1” in the code’s definition refers to the side of the engine that contains cylinder #1, while the “Sensor 2” in the definition refers to the downstream or post-catalytic oxygen sensor.
If the PCM detects a certain level of resistance from the oxygen sensor heater circuit that’s higher than the programmed values, the P0054 code will be stored. This code is set when the powertrain control module (PCM) detects a potential issue with the heater circuit of the downstream (post-catalytic) oxygen (O2) sensor in the engine bank 1. Diagnostic trouble code (DTC) P0054 stands for “HO2S Heater Resistance (Bank 1, Sensor 2).