Signal dwarf lights using Lionel Fast Track and MTH AIU DCS system.

I have reviewed various posts concerning signal lights for switching but nothing has matched my exact issue that i can see.  

I want to use the switch ports to manage the Lionel Fast Track and post a green LED for straight and red LED for turned. I 3D printed some dwarf lights on my cobbled together printer.   With the DCS system I can control the switch but it only sends a pulse and I only get a momentary flicker of the LED.  When I use the ACC port everything works as I like BUT when using the hand held remote OR Wifi App I need to use the Accessories and would like to use the Switches.

I have tried using a latching relay but have not been able to get it to work and I am not an electrical engineer or electrician just a hobbyist of limited ability.

I have included an image of what I am using now.  Any help would be appreciated.

Thank you,



Lionel Fast Track with DCS & Legacy. - Mixed World


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As a furloughed Government employee...I had the time this afternoon to as least figure out how to make your dwarf signal work with the fastrack switch. I had to completely disassemble the switch controller in order to figure out how it works, but I got it done. Really simple...Please see the drawing below. Now to make it work with your DCS system is an unknown to me. But the schematic below is directly from the Lionel controller minus the switches and 1 pair of LEDs.




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gunrunnerjohn posted:

The yellow lead IS the switch position feedback.

Right.  Thanks for the confirmation. 

The wiring I suggested is similar to what jayhawk500 is suggesting and something I figure you can do without purchasing any additional components.  The diode is not need if wired as shown below.  For the resistor, to get started, you can use the 1K you already have (the LEDs will be a bit dimmer).  But you can double up (in parallel) two 1K resistors to "make" a 500 (LEDs get brighter), or put four 1K in parallel to make a 250 resistor which is close enough to the 220 suggested in other threads.  So using just 1K resistors (which presumably you bought in a multi-pack), you can experiment to find a brightness that works for you.



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WOW! - Thank you everyone for all your input.  Honestly this gives me a warm fuzzy feeling (no idea what that feeling is called).  I will hopefully get this bread boarded up today or this weekend and keep you all posted.

I would NOT have figured this out for myself.    

I knew the yellow wire did something but could not figure out what it was doing or how it worked.

Chris - I am so sorry you are furloughed and truly hope you are back to work soon.  I was surprised how many people I have met in the Buffalo area are affected.

Stan - Your drawing is really helpful.

Again, thank you all,


Follow up 

 ****** It all  'just works'! ******

    ******* Thank you *******

AIU to fast track. dwarf lights on a bread boardIMG_20190111_174219247IMG_20190111_174229970


Lionel Fast Track with DCS & Legacy. - Mixed World


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