I was checking the air filter in my s60 and I disconnected the mass air flow sensor thing that connects to the outlet from the air filter box. I forgot to connect it again and when I started the car I got a check engine light.

After reconnecting the light is still on. I read that I could disconnect the negative battery terminal for 30 mins and this would reset it. Is this OK?

If there really is a problem and it is not just recording the stupid thing I did, then it will stay on. Otherwise it should forget what I did and not come back on.

Any thoughts?

 

I guess that would work. Keep in mind that the modules tend to reset and the vehicle needs to be driven a bit for it to "re-learn". As a safety precaution the manual recommends having the key in the II position when reconnecting the battery.

Advance Auto has ODBII readers and they will read codes and clear them for free.

 

I did it and it worked out fine. I did the key in the ignition thing. Car runs fine.