Mars Light for Proto 2000 E-8 : LUSENET : Wiring for DCC : One Thread

I installed a digitrax DH123 in the locomotive, I took out the circuit board and wired the decoder directly to the wires coming of the trucks and motor. I took out the stock lights and put in minatronics lightbulbs. The loco runs great, the lower light works fine off of the F0 button. I wired the upper light to the green wire, which I believe would be F1, the upper light does not come on at all let alone have any type of effect. I'm a little new to CV's and after looking at the manual could not figure out what CV to reprogram or what value to put in. Can you help me out?


Gif Wilson

-- Gif Wilson (, June 02, 2003


Gif, Just installed 4 DH123 with Athearn wiring harness. On the wiring diagram, there is a note that says "NOTE: The Violet and Green leads of the harness are not used bt this decoder." This may be why the green wire doesn't do what you need. This may not be answer you wanted to hear. To save a few bucks, I bought the 123's myself but should have bought the DH163AT's instead. Sorry if I'm wrong. Bob

-- Bob Wingender (, June 12, 2003.

The DH123 does not support F1 on the Green wire as stated. Why not use the yellow wire instead? I don't use a "reverse" light on this loco so the yellow wire is free. The yellow wire can then be made to work off of F1. Change CV50, the yellow wire CV, to x02(002). This will make the yellow wire a Mars light. Then remap by changing CV35 (the remap CV for F1) to x02(002) for the yellow wire. Now it should go on and off with F1. If you also want to make it go on and off with F0 then just make CV50 x42(066). BTW, most railroads used the top light for "Mars" and really were Gyralites [CV50=x47(071)].

-- Kim Parker (, October 20, 2003.

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