Quote:
Originally Posted by ajpletcher Not try to sound like a smart a** or anything (this is a serious qestion), What do you do when changing the battery then? |
Good question!

I did a quick google on the subject and found this page.
OBD 2 was deployed in 1996. So if your vehicle is newer then that I do not recommend that you disconnect the battery to reset the check engine light. First of all remember if you have a hard failure the light will come right back on.
Another reason for this is that the newer vehicles now have a few installed options in them that require a constant supply of battery voltage. I know what your thinking what if you have to replace the battery.
I use a battery tender pluged into the cigar lighter to keep the memory alive.
He goes on to mention a number of other reasons, not to disconnect the battery.
Reset Check Engine Light Procedure