# Problem with MRC decoder



## Bwells (Mar 30, 2014)

I just received a Mantua 2-6-6-2 with a MRC Freedom One decoder with sound. I find that when I put power to the NCE Power Cab that I am using, the loco races off at full throttle for a few feet and then functions normally. It appears that once the loco has had contact with the power cab, everything works fine, just the initial contact sends it on a wild ride. Instructions say to reset default, set CV 125 to 0 but the power cab can't read CV 125. No problem with other CV's, just this one.
I contacted MRC and they said to send it in. I guess that is what I will do but they want 11 bucks to cover return shipping and will not give me a time estimate.
Anyone experience these symptoms or had contact with MRC? Thanks for any ideas.:dunno:


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## mesenteria (Oct 29, 2015)

Try setting CV29 with a value of "34". What that does is to prevent the decoder from sensing track power in DCC as full DC power, which all modern dual-mode decoders do. A value of "38" lets the decoder sense when it's being exposed to DC current so that it can act on the track voltage, say at a friend's layout where it is strictly DC.

Remember that DCC is full voltage to the rails all the time. DC, you must dial up the voltage to get lights to work and for the locomotive to start to move. So, some decoders, for reasons I don't understand, will detect those initial 15 volts in square wave AC when you power up the DCC system and take off like you had just briskly dialed up the DC voltage to full.


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## Bwells (Mar 30, 2014)

Thanks for the quick reply. I did as you said and CV 29 was indeed set for 38 so I changed it to 34 and same thing happened.Any other thoughts? I hate the idea of sending this back and I maybe able to deal with it but I shouldn't have to!!


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## Cycleops (Dec 6, 2014)

MRC decoders do seem rather problematic in general, I wouldn't buy one. Send it back you might eventually get lucky.


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## Bwells (Mar 30, 2014)

Yes Cycleops, I think that is the route I will go and see what happens. I'm afraid it will come back as no trouble found (NTF) but will see what happens. It adds another twenty dollars to the price of the loco but I am hoping it will be fixed. Fingers crossed!!!!


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## CTValleyRR (Jul 26, 2014)

This is one reason that i like to buy my locos DCC-ready and install my own. Thst way I can choose which decoder to install, and test it beforehand.


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## Bwells (Mar 30, 2014)

Update: after a few emails back and forth with MRC, they suggested sending in the loco. On 1-4-17 I mailed it and tracking showed they received it on 1-6-17. On 1-13-17, I emailed them to see if they did in fact receive it. Today, 1-14-17, it showed up! No note as to what the problem was or what they did to it. It was not a new one as it was the one I sent back as the draw bar contains the 8 pin connector with 2 tiny tabs to lock it together. I had to remove some foam in the box in order to fit the loco in without undoing this connection as the top pin is almost hidden. The loco came back with this connection pin on the top missing but it seems good without it. I knew that would happen and mentioned my apprehension as to removing the connector, hence my reason for removing some foam. The loco now works correctly as I assume they just threw in a new decoder. Fast turn around by MRC so all is good except that it just added another 30 dollars to the price! Oh well, live and learn. MRC is okay by me.


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