Q: To pass emission test

Hello. I would need to know what engine you have in your Santa Fe to be able to accurately know what is going on. From the information that I have, it seems like you have an oxygen sensor that is failing. The code is for an oxygen sensor that is functioning incorrectly. It may be caused by a bad sensor, but there may be something else going on with the engine or exhaust that will also cause this. I start by checking the sensor reading with a scan tool to see what it is doing. From that information, I can determine where I need to start with the diagnostic. Most of the time, this is a sensor failure though - especially with this many miles. If you are thinking of having this Check Engine Light diagnosed, consider YourMechanic, as a certified technician can come to your home or office to inspect your vehicle and proceed with proper repairs.