I bought the kit to power up a W by b dummy A unit. Followed the instructions to the T. Tested it by itself and worked great. Put it together with the factory powered A unit and they pull against each other. Put it with another Powered A unit, Same thing. They fight each other. But again by itself it goes the correct direction. I am very frustrated to say the least. Any help is greatly appreciated. But please email Fred directly at darlenewu@cox.net. Thank you.

Have an older (i believe) sd45 drgw 5315.The box is all white with red letters saying williams electric trains.There is no horn, bell ect in this engine.The end of the box says no.4525 sd45 drgw5315.The rear motor has what appear to be diodes (3 of them) going from the motor to a blue wire going to the reverse board.Are these diodes factory? or did someone add them for some reason? The engine will only go in reverse.Any and all help and or advice will be greatly appreciated.I can be contact directly at darlenewu@cox.net Thank you.