I’m in the proces of permanently coupling two MDC Criiters together to eliminate stalling on turnouts. The Critters are equiped with led’s for directional headlights. When I’m done, I would like only the headlight on the lead locomotive to come on. I don’t want the headlight on the trailing unit to light. Can I just cut the wire to the other diode? Are there any other options?
Any information, guidance, or suggestions would be greatly appreciated.
Tom
Yep. Just put a peice of tape over the end of the wire after you cut it.
Cut one of the wires that goes to the bulb/led/whatever light source is on the end of the locomotive.
Easier to fix then cutting a leg of a diode. 
You SHOULD be able to cut the lead to the Diode to get the effect you want. Just be aware that LED’s do NOT take REVERSE VOLTAGE very well and can blow. Maybe it is set up so that one of the LED’s protects the other in reverse direction You should solder in a regular 1N4004 or similar in series with your Headlight and its dropping resistor to protect the LED when your loco(s) go backwards. Otherwise you should be OK!
Cheers from Down Under
Trevor www.xdford.digitalzones.com FYI
That is a good point. If the front and rear LEDs are protecting each other you’ll need to be more creative. So a little more research is needed first!
Thanks for the help everyone. Can you tell from looking at the enclosed pic whether I need to add the diodes?
Tom
PS I’m assuming I need to wire the 1N4004 to the negative leg of the diode?
The only thing you need to do is cut one of the wires to the light(s) that you want to disable, and insulate the end of the wire so it doesn’t short against anything.
Thank you! That was the answer I was hoping for.
Thank you everyone for your help on this.
Tom