I have two of these units. They are well detailed and smooth running. Well, at least one of them is. The troublesome unit has a bad light board. When I first plugged a decoder, the unit shorted out the DCC system. I was able to fix that part, but now whenever I plugged the front headlights in the board, they remain constantly on even when the function button is turned off.
What is causing that? I will probably contacting Athean to see about getting a new board.
It sounds like part of the light board is contacting the frame, causing a short between the decoder’s light outputs and the power supply. I’d compare it with the board from the good unit to check if there were any metal bits sticking up that shouldn’t be.
You might also like to check the light outputs of the decoder in the ‘bad’ unit - chances are that the short may have blown these.
Which decoder ? (brand name, type) On many decoders, you can change CVs 49 and 50 to several different values that have an effect on the lights. Read the documentation that came with the decoder.