Bachmann Programming Issue

[abbotttl]

I have a new Bachmann "DCC On Board" diesel which is behaving very oddly when attempting to program - that is, in every mode of my Digitrax Zephyr (Ops, Page, Direct, Physical), I get the "d nd" error message, which corresponds to basically an open circuit and no power draw.

The decoder appears to be fine, operates fine, I have control over lights, etc... but I can't program a thing on it, even to change the address.  As far as the programming is concerned, it can't see an engine at all. 

My only other DCC engine is a Broadway Limited, and it can be read/written just fine, so I'm pretty sure it's not the track - though at this point I'm starting to wonder if I have a slightly low voltage due to a bad connection somewhere that's distorting the waveforms just enough to affect one system and not the other...

Any ideas?

Thanks!

[selector]

Hello.  About a dozen thread titles down on this page is this thread.  It may help you out.

http://cs.trains.com/trccs/forums/t/152332.aspx

[jeffrey-wimberly]

I have some locos that are equipped with Bachmann decoders that do the exact same thing. The only way I can get my Zephyr to see them is to connect a 12 volt light bulb (structure light) to my program track. Once I do that I can program any of them. I think the problem is that the Zephyr doesn't get enough resistance from the decoder.

[abbotttl]

 

Thanks all!  Glad to see that my problem is fairly common, and that there seems to be a way around it!  Will try the light / resistor trick and cross my fingers.

Thanks much!

 

[DigitalGriffin]

NMRA protocol states the train is supposed to respond by putting a load on the programming track.  This is usually done with a movement of the motor.  You see most decoders advance the train a lil bit when programmed.  But certain decoders like MRC, and cheap Bachmann DCC just don't work right because they don't send the response in time.

The good news is a number of manufacturers (NCE and the latest Lentz) are increased the response time and charge up time before they indicate failture.  So program boosters may no longer be necessary.

[abbotttl]

Thanks to all who replied - the resistor trick worked like a charm.  =)

I'm off and running!

Thanks again,

Troy