P0051 - OBD II Trouble Code

Our automotive experts have put together the following information about the P0051 diagnostic trouble code. We've provided the common symptoms that occur when this code is set along with the frequent repairs that address the issues related to the P0051 code.

What Does P0051 Code Mean?

OBD-II Code P0051 is defined as a HO2S Heater Control Circuit Low

The purpose of the oxygen sensor is to measure the oxygen content in the exhaust gases after they leave the combustion process of the engine. The oxygen sensor must be at a certain temperature in order for this information to be accurate. The oxygen sensor has a heater wire inside to help bring the sensor up to temperature quicker. When the PCM detects the heater wire is not operating, it will set code P0051.

P0051 Symptoms

• Decreased engine performance
• Increased fuel consumption

Common Problems That Trigger the P0051 Code

• Oxygen sensor failure
• Powertrain Control Module (PCM) failure
• Wiring issue

Common Repairs Needed for the P0051 Code

• Oxygen Sensor Replacement