I've never had trouble programming before but this has me stumped. I connected one wire to Programming A to the rail of a separate piece of track. I connected the other wire (Programming B) to the other rail. I have alligator clips soldiered on. It's all a great connection. So I put the loco on the track, Press the Program key, Press the PAGE key, press the AD2 key, enter the loco number I want to change and press the CV-RD key and then get the d nd error time and time again. I checked the connections a million times. I used different locos. What am I doing wrong here????