I have a brass steam engine that the drawbar between the engine and tender came off of. Because I am using DCC and the drawbar is not now used for electricity I just put it back together not thinking it had to be insulated. When I put it on the track it shorted out the system. I took the engine off the track after a few seconds and put the drawbar back together more carefully. When I put it on the track the lights work but the engine doesn't run. The other engines do. I checked for broken or burnt wires and couldn't see anything. I pushed to make sure the harness and decoder were plugged together good. It is a Digitrax DH163D decoder and I am using a MRC Prodigy Advance system. Can you wreck a decoder this easily? This engine used to run really nice. I have another brass engine that didn't run too well and I have spent a lot of money getting it to run good, but it now on it's 3rd decoder of the same make as above. I think the first 2 were because it didn't run very good and burnt out the decoders. Am I using the wrong type of decoder? I only want engine and lights in the decoder. This is getting expensive and frustrating.
Any help and advice appreciated and thanks in advance. I want to run these engines and not just have them for display.
Barry
Yes, it doesn't take much of an overload or short circuit on a decoder to damage it.
Have you tried resetting or reprogramming the decoder? If you can't perform a factory default reset or reprogram any of the CVs in the decoder, then it is probably toasted.
It doesn't take much to pop a decoder. Put the loco on your program track and see if you can read CV7 and CV8. If the decoder reads back then it is probably good and just needs to be reprogrammed. As for putting decoders in Brass steamers. You need to find out the current draw of the loco first. Some of the old open frame motors and gearboxes draw a lot of amperage. If the decoders are running at the maximum current rating they will heat up and smoke after awhile. If the stall current of the loco is 1 amp then I would look for a decoder that has 1.5 or a 2 amp rating.
Pete
I pray every day I break even, Cause I can really use the money!
I started with nothing and still have most of it left!
I tried reprogramming it, how do you reset it.
CV7 reads 051 and CV8 reads 129. The headlight turns on and off but the engine doesn't move.
Reprogram the address and try again. If you give it a long address, set CV 29 to a value of 34.
If the motor doesn't run after doing this, then the decoder is history.
CV 7 value of 51 means the decoder has software vesion 8.1 and CV 8 value of 129 indicates that it is a Digitrax decoder. Being able to read these CVs does not indicate whether or not the decoder has been destroyed, however, because they are CVs that cannot be changed by the end user.
Factory reset for Digitrax decoders is programming CV8 with 8. It won't read back that value - it will always read 129 for the Digitrax manufacturer ID, but if you write 8 to it it causes the decoder to reset to the defaults. It can then be address as 3, or reprogrammed as needed.
The bad news is, if the short occured in a way to connect the motor wires to the track, you've blown the output of the decoder and while it may read back and program just fine (and you can probably turn the lights on and off), it won't run the motor.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Thanks for all the help, I guess it is toast.
williamsbWhen I put it on the track it shorted out the system.
Barry,
You don't indicate it in your post but this is why it's important to operate your locomotive on the programming track first BEFORE you put it on the track. When in programming track mode, your decoder doesn't receive full power like it would on the layout. Programming mode is not only important for addressing your locomotive but also for testing it so that these sorts of scenarios are minimized.
Tom
https://tstage9.wixsite.com/nyc-modeling
Time...It marches on...without ever turning around to see if anyone is even keeping in step.
If you can get to the decoder easily, examine the plastic covering. Look for a small round spot that's black or brown. This usually indicates "burn through" as the decoder overheated and burned out a component, burning through the plastic coating as well.
It takes an iron man to play with a toy iron horse.
I have similar problem. I have a BLI steamer using the QSI system, and I have an NCE Power Pro setup.
I get cannot read CV's and when I take it off the program track and go to the main track, I get sound(bell-whistle, air sounds, etc, and headlight off and on,) but it will not move. Tried progeram on main, but same results.
Not sure if the QSI is asking for more current than the power pro can deliver for programing either on program track or the main.This steamer is a J1 BLI, brand new, but several years old. My T1's, same basic setup took programming, they are BLI QSI system.
I'll try a factory reset, by removing and replacing the jumper in the tender.
TheK4Kid
The decoder may be in "shut down" mode. Download the QSI Technical Reference Manual from the BLI web site and read through the 'startup' and 'shut down' procedures of the decoder.
But first, try pressing F6 twice. That may wake it up.
Try programing CV19 =0. Before you do a reset. Also try double pressing F6 the loco may be in disconnect mode. Programing QSI decoders on the program track works better if you turn off the verbal feedback.
Thanks for all the help here, a lot of good advice and lessons learned. Because I bought a decoder that can be unplugged I am going to send it to Digitrax for repair. I rushed my original repair and caused the damage, better to be patient, I could have saved a lot of time and frustration by not hurrying. Also because I have been running this beautiful engine for a couple of years I just plunked it back on the main track because it had already been programmed. After feeling bad initially, these posts have helped me feel better and realize it really is not so bad after all.