Model Railroading > Kato SD40-2 snt LED problem

I have this unit, the first with the bright LED's
When I ran it on straight DC.and not on my DCC it worked fine the LEDS came on bright and the lights reversed when changing direction.
So I now install one of my Digitrax decoders, a DH84 which I have removed from a unit I'm selling and works fine; into the SD40..I never bothered reprograming it as what was there was OK..
Turn everything on, great , turn on the lights, fine, when I reverse the lights change direction; great. Turn off the light, their out, all seems fine but then I notice that the LEDS are still on, but at a very low brightness???? Anyone got an answer on this???

It probably has something to do with the voltage on the LED. I can't say this for sure.

Tim Hardesty

I have had this problem with blue, white, and high intensity red LEDs. They are so bright that they will light just a little bit if there is any leakage current. A normal LED still has this current but does not generate enough light to be seen. I've been dealing with circuits that I am designing, and have had to change my design to eliminate the leakage current. I'm not sure just how to fix this problem with a DCC decoder, perhaps a resistor innseries with the LED, but that would also dim it when it is on. I would contact the manufacture of the decoder to see if they have any suggestions. In any case, it is a design flaw, nothing you did wrong, not a defective decoder, and will do no harm to the decoder or LED.

Thats what I thought, but I needed a second opinion... I use to marked these type of components...
I'll contact Kato.. regards