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P0042 Severity
Once the vehicle's onboard system no longer detects the issue, most codes will disappear on their own. If your vehicle still has this code, however, it should be properly diagnosed to avoid a more serious problem.
For a proper diagnosis, RepairPal Certified shops have the equipment, tools, and expertise.
Moderate severity codes might not threaten the vehicle's safety or functionality immediately, but you should still get it diagnosed within a reasonable time frame to keep your car running well.
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 P0042.
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OBD-II Code P0042 is defined as a HO2S Heater Control Circuit
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 P0042.