Hi all,
I just got back into the hobby a little while ago and I am very new to DCC. I bought myself a digitrax zephyr for my layout. I jsut got it all wired today and have been enjoying it so far. One problem I am running into is that when I try to change an address on a decoder the d nd error message pops up. I know that is says in the manual that it means there is an open circuit but what does that mean to a layman? How do I resolve this issue?
Thanks,
Jim
I've got a Lenz DCC system, but I think the terms are pretty similar.
I order to program a decoder, it needs to be on a "programming track." This is a separate piece of track connected to separate terminals on the base station. Do you have something like this?
Next, the locomotive must be on the programming track, and it must be properly wired. One of the nice things about programming is that it uses much lower power, so you can actually test the decoder wiring, at least to first order, to make sure it's good before applying full power on your layout.
Did you buy this engine with the decoder installed, or did you install it yourself? The particular test that's done is to make sure there is a motor connected to the decoder, so if you're trying to program it without a motor, that would be your problem.
It takes an iron man to play with a toy iron horse.
Jim I am one step behind you in the hobby. However Google tells me this error happens with Bachmann locos. Would that be what you have?
If not, what decoder is it? More details are always better.
Henry
COB Potomac & Northern
Shenandoah Valley
What it means in layman's terms is that there isn't a complete, unbroken electrical path between the Zephyr's PROG A and PROG B outputs and the decoder you're trying to program.
If you haven't yet, read and understand section 16 in your Zephyr manual. Disregard the parts about Ops Mode Programming (for now). Follow the instructions and diagrams to set up a programming track exactly as outlined there.
Make sure that the connections between the PROG outputs and the track are electrically secure. (Keep in mind that unlike the TRK A and TRK B outputs, there is a ground connection between the two PROG outputs. It's not used for programming, so make sure you're connected to the correct terminals.) Also, make sure that the programming track and the loco's wheels are clean.
If all that checks out, the problem could also be in the loco. Try reading another decoder-equipped loco if you can, preferably one without sound.
I was refering to this, found on the Digitrax site:
"Some Bachmann decoders have difficulty programming and need to have a 1K ohm resistor installed between the PROGA and PROG B outputs during programming to give them the help they need to accept programming sent by the command station."
First thing to check is that you have actually connected your programming track to the Prog a and Prog B terminals. This may sound elementary but it has happened more than once. your programming track should not ever be connected to the TrackA and Track B terminals at the same time.
Make sure you are in the proper programming mode. Each time the Program button is pressed, the mode changes. There are 4 choices. You want either Pg (page mode) or Pd (Direct mode). Digitrax recommends Page mode but quite frankly, I have found Direct mode to work better on many non-Digitrax decoders. It works well on Digitrax too.
In order to help further we really need to know what you are trying to program. There are some little tricks that can help for certain decoders. that 1K ohm resistor trick works for some but not all.
Martin Myers
You can get a dnd message if you are trying to program a sound decoder on the program track. The higher current required by the decoder is the probable cause. I have encountered this with my Zephyr and my Zephyr Extra while trying to program Tsunamis.
Joe
I ran into this exact problem yesterday. I've been rebuilding a Bachmann 0-6-0 that came with factory DCC. I removed the smoke unit, added weight and am working on rebuilding the boiler into a reasonable representation of an IC engine.
I took the chassis and valve gear over to the track and it ran great on address 03. I put it on the programming track to change the address and got that error message. I rewired the programming track twice, coudn't fix it. I put it on the main and managed to change the address in OPS mode. But all of the rest of the values changed. I had no lights and slow speed operation was terrible (it crept along before I tried to program it took about 90 seconds to move 3 feet).
I'm debating on if I should pull the Bachmann decoder out and just upgrade to sound, but I have several Bachmann DC on board locos and I'd really like to solve the problem. Guess I'll call Digitrax on Monday.
JWhiteI ran into this exact problem yesterday. I've been rebuilding a Bachmann 0-6-0 that came with factory DCC.
There has been discussion here from time-to-time about Bachmann's use of "RFI" radio suppression choke coils/capacitors used in their motor wiring.
https://sites.google.com/site/markgurries/home/technical-discussions/decoder-motor-drive/motor-capacitors/bachmann-engines
These can mess up programming and BEMF circuitry on DCC systems. As far as I remember Bachmann has to have this choke for E-U requirements but not for North America but they keep it in anyway.
On the very few Bachmann engines I have I removed their board completely. The TCS website has an example of how to remove the capacitors.
Hope this helps, Ed
JWhite I ran into this exact problem yesterday. I've been rebuilding a Bachmann 0-6-0 that came with factory DCC. I removed the smoke unit, added weight and am working on rebuilding the boiler into a reasonable representation of an IC engine. I took the chassis and valve gear over to the track and it ran great on address 03. I put it on the programming track to change the address and got that error message. I rewired the programming track twice, coudn't fix it. I put it on the main and managed to change the address in OPS mode. But all of the rest of the values changed. I had no lights and slow speed operation was terrible (it crept along before I tried to program it took about 90 seconds to move 3 feet). I'm debating on if I should pull the Bachmann decoder out and just upgrade to sound, but I have several Bachmann DC on board locos and I'd really like to solve the problem. Guess I'll call Digitrax on Monday.
Digitrax website tech support information states:
"Some Bachmann decoders have difficulty programming and need to have a 1K oh, resistor installed between the PROGA and PROGB outputs during programming."
Please note that this will not work with all decoders, nor will this fix all issues, but it will help Bachmann decoders, and this is a known problem.
Back to the OP: A d nd message simply means the decoder is not responding, could be a wiring problem with the programming track, the decoder itself, or simply that the decoder requires more power to program (if sound equipped.).
Ricky W.
HO scale Proto-freelancer.
My Railroad rules:
1: It's my railroad, my rules.
2: It's for having fun and enjoyment.
3: Any objections, consult above rules.
As mentioned above, if you have a Bachmann engine with a Bachmann decoder a 1k ohm resistor across the programming track should help. According to Digitrax it fools the programmer into increasing the amperage to the programming track. Many of the early Bachmann decoders were low-end Lenz decoders. I've had the same basic problem programming some of them.
Below is a photo from my website of my 1k ohm resistor in place on the programming track. The same trick sometimes works with sound decoders though I've never had a problem programming them with my Zephyr.
Sorry for the poor quality of the photo, but it gets the point across.
Remember its your railroad
Allan
Track to the BRVRR Website: http://www.brvrr.com/
Thanks, that solved my issue!
UPNorth906Thanks, that solved my issue!
That?
As in you hadn't properly wired the program track? Or
You had, but needed a resistor?
Had the exact same problem.I finally took it in to dealer, was told something inside was not right. I had sent it back to Co. for repairs once already. the unit must be 10-12 yr old. It ran the trains fine just would not program, Icould live with that.
Coulpe weeks ago LHS had the ''EXTRA'' on sale ,so I got a new one.
You'' may '' have an problem in the unit