Programming Troubles with my DD40AX

[Magikthise]

Hi all.

I recently switched from HO to N scale and one of my first purchases was this non-sound model with DCC On Board.  I'm very pleased with its operation, but here's the conundrum:

I can't re-program the loco's address from the factory '003' to the engine's number (6910).  Nor can I 'read' the address - that 'd_nd' error keeps coming up.  I have a Broadway Limited decoder-equipped E8A (with sound) and had no problem reading and changing the address but I'm at a loss to figure out why I can't do the same with the Centennial.

I'm using a Digitrax Zephyr system with a stand-alone programming track.  It's been suggested that I purchase an add-on booster for my programming track (ie. a Digitrax PR3) because the Zephyr system doesn't have enough voltage.

Any help would be appreciated.

[railtwister]

I have had this problem come up a few times, and when it wasn't caused by dirty wheels, poor connections, or loose plugs, I have switched programming modes from direct to paged, or vice-versa. Sometimes a decoder will program in one mode and not the other. I don't have a Zephyr, I do all my programming with a SPROG II, JMRI DecoderPro software, and my Netbook computer.

Bill in FtL

[Magikthise]

Thanks for the quick response, Bill.

I should've mentioned that I tried re-programming in both paged and ops modes with no luck.  I wouldn't think the wheels are dirty as the model was only a few days old when I attempted the re-program.  And considering I was able to re-program the E8A, loose connections shouldn't be an issue.

[Magikthise]

Ok, I've re-tried changing the address, still with no luck.  So...

Can anyone advise me as to how the shell comes off?  I'd like to check to make sure the decoder isn't wired incorrectly.

[James in FL]

I can't help you with the DCC.

Spookshow tells you how to remove the shell here:

http://www.spookshow.net/loco/bachdd40ax.html

Good luck

[Brewman]

If the locomotive is operating fine other than programming, I don't think it would be wired incorrectly. I have read that sometimes a resistor needs to be wired across the track leads for some decoders to program. I did not have that problem with mine but I use the Digitrax PR3 with a program track and JMRI for my programming.

[Bucksco]

The following is from the Digitrax website:

There are decoders now present in the market that do not draw enough current for the programming track to reliably detect that they are present, hence the error report of "d-nd". All you have to do is to use a 1K 0hm 1/4 watt resistor across Prog A and Prog B outputs during the program process and it will program the Lenz/Atlas decoders. Some of the new Digitrax decoders also require this same approach.

"d nd" is the error code for decoder not detected. This problem can also arise if the locomotive has dirty wheels or the programming track is dirty, with the dirt interfering with current flow.

[skipgear]

Which Zephyr do you have? If it is a Zephyr Xtra, you don't need a programing booster as this model has it built in.

Try programing on the main in paged mode.  Make sure you remove all other locos from the main or they will be programmed to the same address. If that doesn't work, then try the resistor across the rails on the program track. If you have a Zephyr Xtra, that should not be needed though.