i have a 1993 190E and i don't know how to reset the o2 light (if it is even possible). i have replaced the oz sensor and was hoping the light would go out by itself but of course it didn't, that would be too easy. so, is there a way to reset this?? do i need a code reader? is there a magic button to push? i did the whole battery thing and that didn't work. any help on this subject would be much appreciated.