Q: I took my car to Advance Auto and them do a check engine light diagnostic test and the code is C0245

asked by on November 30, 2016

I bought my car 2 weeks ago and the check engine light keeps coming on.. I took it to get a diagnosis test done and it read wheel speed sensor frequency malfunction... Mil - not requested Since last key cycle-pass Since Dtcs erased-pass Code # CO245

It also read code#PO420 Catalyst System Efficiency below thresholds Bank 1 MIL -Requested Since last cycle - Not Run Since Dtcs erased- fail

My car has 193082 miles.
My car has an automatic transmission.

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Hello. Thanks for writing in. You may have two separate issues going on at once. The speed sensor code is likely due to sensor failure, or a bad connection. In the case of a bad connection, a good visual inspection may solve the issue. If the sensor has failed, it should trick some other codes as well. The P0420 catalytic converter code is telling you that system is detecting a problem. Its a relatively open ended code, but the system is not very complicated. The Catalytic converter may have failed, the oxygen sensor after the catalytic converter may have failed, the wiring connection may be lose or worn, or several other miscellaneous issues. You are going to want to handle both of these issues separately at first until you have reason to believe they are related, which is unlikely. If you receive another check engine light, make sure you retest the vehicle for codes.

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