Lionel U33C Wiring for Lights I have removed all the Lionel electronics from my U33C locos, so that there are only two small plugs hanging from the front and one from the rear. I think I have decoded the wiring system for the lights. I experimented with good old low-tech dry cells and found that one of those (1½ V) will light the red marker lights at each end. The other lights required two cells (3 V).
These voltages are the minimum to get light, but may well be sufficient. I did not experiment to see how much voltage they can handle before they go out (for ever). The lights are, of course, LEDs, and, being diodes, they light only with proper neg/pos orientation. Where I give a wire colour combination, the first one is the negative connection, the second is positive. Rear There is a 5-connector plug with the following wires, from left to right. Black, Red, Grey, Double Black, Double Red Black / Red @ 3 V lights the main rear "head" light. Black / Grey @ 3 V lights the rear number boards. Double Black / Double Red @ 1½ V lights the 2 red marker lights Front The 2-connector plug. Black / Grey @ 1½ V lights both red marker lights. The 4 connector plug has wires, from left to right: Black, Grey, Red, Blue Black / Blue @ 3 V lights the headlight Black / Red @ 3 V lights the number boards Black / Grey @ 3 V lights the cab interior - This is the one that I think the manual says lights only when stopped or at low speed. At track speed it goes out. Tom Hawley -- Lansing Mich
