Im trying to install a Digitrax DH163AO in an Athearn Genesis SD70M. I am having lots of problems. The lights will never work. The motor functions are all that works. I am using 1.5 volt bulbs with 680ohm resistors, one in series with every bulb, I use this light set up with every Athearn lcomotive I have and it works. I thought I had a bad decoder, and tried another and messed them both up. So I sent them back to Digitrax and got replacements and installed one and ruined that one. I thought it was me then. So I went to the other SD70M. Still Athearn Genesis but different road name and I think its a newer model. I installed a DH163AO in there the exact same way, and the way the instructions say, and no problems. Lights work, motor works, and the ditch lights work. I cleaned all the wheels, contacts and everything thing else that carries the signals on the SD70M that does not work, but it did not help. I don't understand. I posted this in HO Forum too because I wasn't sure if it was a DCC problems or a locomotive/manufacturing problem. Thanks for your help.