How do you reset the check engine light on a 1995 Mercedes Benz E320?

I have a 1996 C280 and the way I reset the light (given off the record by a mechanic) was to unhook the negative battery cable, wait 15 sec and rehook. It was done.... problem(s), only one if you are not prepaired. The radio is anti-theft capable, you have to have the correct code for it in order to use it again. If the code is put in wrong more than 5 times it locks out for 1 hour. If it is put in wrong after that you have to go to a dealer to reset it. I would think your vehicle would be them same for the reset.