Chrismas Train LED puzzle ?

[dragonbusa]

Well I started work on our Christmas train, its going to be a figure 8. One loop around the tree and the other an HO Christmas seen. I took one of my old F9's and installed color change LED's in the head light and in the four holes in the sides. Also the caboose (its a spot light caboose) Its works great on the bench power supply all the lights change from red-blue-green. But when I put it on the track all the lights stay red, none of them will change. I can put the caboose on the track by its self and it will change colors but as soon as I put the loco on it goes to red and stays that way. Any help would be greatly appreciated. I cant figure out for the life of me and I have tinkered with it for hours. I tried wiring it in parallel and in series same result.

[Joe Satnik]

Dear dragonbusa,

When you say " one of my old F9's" I assume you are using a variable DC power pack.

Turn down your power pack speed control until your caboose LED stops changing colors.

Read and note that DC Voltage on the track rails. 

Compare that to the DC voltage on the track rails with your loco on the tracks. 

My guess is that your LEDs will work, but at a track voltage that would cause your loco to fly off the tracks on the curves.

If you installed a switch in one of the motor wires, you could park the loco and just display the LEDs. 

Hope this helps.

Sincerely,

Joe Satnik