O2 sensor(s)

I have 2011 Jetta TDI wagon, 6-speed. The car has about 34,000 miles on it, so used relatively little. It has been well maintained. The car has the VW emissions modification.

Because of a minor starting issue, the battery connectors were removed to clean the posts and the connectors. The timing of this could not have been worse, since the car was due for inspection and disconnecting the battery clears all the emissions monitors. So when I took the car in for inspection, it failed, due to the monitors not being ready. I was advised to just drive the car (the inspection was done by my local VW dealer and the car now has a 60-day sticker on it in compliance with state law) and, indeed, after 100 miles, all of the monitors indicated "Passed" with my VAG401 except the O2 Sensor(s) and AC.

Anyone know anything about the AC bit? I've seen things from searching online that suggest that there is no diagnostic that will change that bit, but the information about all this is not good -- a lot of the descriptions are poorly written and contradict each other. I'm guessing the state inspection (Massachusetts) won't even look at this bit, but that's just a guess.

As for the O2 sensor(s) bit, does anyone know of a particular driving procedure that will get the O2 sensor testing done? I believe that in my case, the diagnostic simply hasn't been done or completed. I don't think it has actually failed (though the scanner does say "Failed"), because there are no DTC codes.

Any information you might have about the AC and O2 sensor(s) bits would be appreciated.

Thanks --
/Don Allen

I don't think our gen car monitors the ac for leaking, so that monitor is probably not used/ installed/ ignored etc.. as for the o2 sensor, you should be able to get a pass with one unset readiness marker, at least that's the rules in ny. if not then your extended emissions warranty should compel vw to fit it for you free of charge.

O2 sensor is covered under extended emissions warranty.

Thanks to both of you for the good information.


I didn't know that the O2 sensor was covered under the extended warranty, but my suspicion is that it's ok, just not set. I say that because there are no DTC codes. But if it needs replacing, this information will be useful.


As for having one of the diagnostic bits unset, I checked and the NY rule comes from the EPA and I believe it is also the case in Massachusetts. So I think the car should pass now. I'll give it a shot and go in for re-inspection.


Thanks again to both of you.


/Don Allen

Mice chewed through my rear/downstream 02 sensor wires over a year ago... no MIL.

I'd just line up a loaner at the dealer and have them fix it while it's free.