Did you ever get the decoder to work? Out of curiosity, which particular flavor DCC system do you have? And what values have you tried to put into those CVs?
Maybe by bumping this post up with the additional info you might catch someone's eye who missed it the first time around.
cv 51 does nothing and CV 2,3,4 all change and I can read the changes on the command station but it doesn't have any effect on the loco I have three of these atlas loco with a 342 decoder and none of them seem to change the response of the loco at all
Instructions are: http://www.atlasrr.com/pdf/4FncDecoder_Manual.pdf
Looks like you have to set CV 51 to get it to operate like a Mars light.
CVs 2, 3, and 4 are shown in the instructions, so if they "don't change anything" either the decoder is bad or you are doing something incorrectly.
does any one know if you can set the light to a mars with this decoder also cv2 & 3 don't change anything
I know these are low end decoders but there should be some cv programing