how do I reset radio after battery disconnect?

You need a trip to M/B dealer with proof of ownership, to get unlock code. BUT@ http://www.slkworld.com/slk-r170-general-discussion/19877-radio-code.html .those guys say you can with a phone call and VIN# if you bought your car from them, have your credit card ready, there may be a fee

Okay how do I unlock the waiting to reset the code how do I unlock the waiting to reset the code even after taking the cable off in the waiting is still on