If possible, take it to a hobby shop or a friend's layout who has DCC (or better yet, Decoder Pro) and read the CV's (control values) for the decoder. It sounds like one of the CV's that controls engine speed might somehow have gotten changed.
Greetings all. I am a newbie to the model railroading. Recently purchased a Kato sd 40-2 with a Loksound decoder. I was trying to operate the loco with an MRC tech 6 sound controller. The first time I tried to run it, the loco powered up with engine sound at idle, but would not respond to the throttle input. Then followed the mrc instructions for programming still no movement. I try to operate again, power up the engine, sound starts up, then the thing goes to full throttle and races away. No matter the throttle input, the thing stays wide open. What is going on? Any help is greatly appreciated.
Bryan B.