Do you know what a H02S12 means cause I have 2 codes coming up with service engine light ?

Slomad you are not correct, It depends on the diagnostic code of the o2 sensor malfunction the o2 sensor can be miss diagnosed with that theory, considering its function is to measure the oxygen level in the exhaust there are many factors to cause a false positive with a o2 sensor, like a bad catalytic converter, for instance especially if the code was o2 sensor slow switching e.t.c if the cat was bad it would provide less oxygen content. There are many other factors, you should study the lambada and what it means. I would also like to facillitate an exhaust leak could cause a false positive on a malfuntioning o2 sensor. That is what diagnostic is for. You mention a bad connection but what about a bad pcm or faulty wiring. Hope this info helps instead of just throwing parts at a car money is hard to come by with this economy. Slomad you are not correct, It depends on the diagnostic code of the o2 sensor malfunction the o2 sensor can be miss diagnosed with that theory, considering its function is to measure the oxygen level in the exhaust there are many factors to cause a false positive with a o2 sensor, like a bad catalytic converter, for instance especially if the code was o2 sensor slow switching e.t.c if the cat was bad it would provide less oxygen content. There are many other factors, you should study the lambada and what it means. I would also like to facillitate an exhaust leak could cause a false positive on a malfuntioning o2 sensor. That is what diagnostic is for. You mention a bad connection but what about a bad pcm or faulty wiring. Hope this info helps instead of just throwing parts at a car money is hard to come by with this economy.

I said "typically" I didn't say always. And if the catalytic converter was bad he would have other codes in addition, not a O2 sensor heater circuit code only. If he had cracked manifolds he'd throw a code, but not for the heater circuit. Sure a bad PCM/ECM could be the problem, but without a scan tool or more information you couldn't say. And nobody said anything about throwing parts at it. A bad connection is a cheap fix, and replacement O2 sensor can be a cheap fix depending on the se?or or car line, but replacing PCM's, catalytic converters and the such is going to cost way more in terms of throwing money and parts at a car. I said "typically" I didn't say always. And if the catalytic converter was bad he would have other codes in addition, not a O2 sensor heater circuit code only. If he had cracked manifolds he'd throw a code, but not for the heater circuit. Sure a bad PCM/ECM could be the problem, but without a scan tool or more information you couldn't say. And nobody said anything about throwing parts at it. A bad connection is a cheap fix, and replacement O2 sensor can be a cheap fix depending on the se?or or car line, but replacing PCM's, catalytic converters and the such is going to cost way more in terms of throwing money and parts at a car.