My CN/CN-GP decoder installation does not run, and I believe I installed it properly.
The most common problem with a CN or CN-GP installation is not properly isolating the motor from the frame. It is crucial that you take great care while soldering the motor tabs to prevent developing points, or leaving too much solder which will short against the frame. This problem can catch even the most expierenced installer off guard, so we recommend testing the the frame and motor for contuinity with a multimeter prior to powering up the locomotive. This problem is especially common on the bottom side of the motor, and extra care should be taken to avoid this common mistake.