I'M sorry about not saying (I'm new to forums) that i'm useing a bachmann EZ Comand and 3- EZ decoders. On 2 antherns road switchers (20 yr's old) and a bachmann F3a with circut board installed. Every thing works fine. The problem is that the blue and the white wires on the Bachmann decoders won't lite the bulbs, and the bachmann engine that came with the EZ command kit, light will not come on either.. So the question is what light bulb do yous recommand?? Jerry