I like to start with the simplest thing first.
I've had situations where I've taken an engine apart trying to figure out why it quit running, and it turned out while adjusting a CV I accidently did something that changed the ID number or say changed a CV so the decoder no longer allowed extended addresses. Once I programmed the address back in, it worked fine.
I'd put one on the programming track and read the ID (assuming your system can do that - although I think most all do). Or just try programming in a new address like 03 and see if it responds to that.
I will have to see what i find next sunday if time permits.
A pessimist sees a dark tunnel
An optimist sees the light at the end of the tunnel
A realist sees a frieght train
An engineer sees three idiots standing on the tracks stairing blankly in space
Locomotives do that some timess. The fireman (conductor) will have to go and reset the breaker, of if that is a no-go they may swap engines somewhere.
ROARING
The Route of the Broadway Lion The Largest Subway Layout in North Dakota.
Here there be cats. LIONS with CAMERAS
if nothing make sense (a common refrain from work), rather than try to find the problem, verify what works.
i had a problem with a decoder that would drive the wheels a fraction of a turn then stop and verified this behavior before finally resetting the decoder.
in your case, since you mentioned a contact issue with the truck, i would try testing the decoder with clip leads connected to the track connections of the decoder.
if the wheels don't turn, check if the lights can be controlled.
if the lights work, disconnect the motor connections and measure the voltage on the motor leads, in both directions. If there's voltage in one direction but not the other, a good guess would be that one of the 4 h-bridge transistors has failed (i.e. burned out).
if the lights don't work, can the controller read anything from decoder. if not, i'd try checking for ~5VDC to the processor.
if there's no processor voltage and you have a direct power connection to the decoder, i would guess the regulator failed failed.
if the controlled can read the decoder, try reseting the decoder (if you haven't already). I have no explanation for why my decoder (T1) spun the wheels for a partial rotation. have no idea what CV settings can cause that. But a reset fixed the "bizarre" problem.
greg - Philadelphia & Reading / Reading
to answer the questions from Rich
The type of dcc system is nce power pro. this one dates to 2003. not more than two years older than the three atlas locos in question. At that time, Dcc was an option and dual dc/dcc boards were not around yet. These three were bought non dcc equipped.
The loco that quit yesterday (1504) has a NCE decoder. hard wired in, mounted using the foam tape method. The other one (1505) that quit two years ago has the original factory board with a QSI sound board plugged in. The boards in all three were installed not long after purchase. so they have had many years of running with these boards.
The concicts were completely cleared. I have not had a chance to try reset 1504 on the progam track, but 1505 was in an earlier attempt to restore it.
In checking the maintainance cards 1504 was found to have an electrical issue in the front truck early on that caused it to not make full contacted. the rear truck was fine. bending the contacts fixed it. 1506 (the third one of the group) also had that problem. 1506 is the laast one standing.
Toms question
1 Is there an issue with these an motor brushes contacting the motor? The visual glance I gave them this morning looks to be a yes they are isolated. but further bench test is needed.
2 The 1505 qsi board does have the insulation on it. 1504 does not. That was my first thought, was there a wire connection worn bare, but nothing found on inspection.
What prompted me to ask if there is outstanding issues with this early run I might have missed come from Kato. Remember the sd80 MACs and the short they had from a metal tab 1/16 too long. In dc it was fine, but dcc it wreaked havoc with boards. I am wondering if an issue similar persists somewhere in these early dcc wired locos.
*Two locos, two different dcc boards, one hardwired, one factory wired with a plug board both stopped dead in mid run after running for a while.
*Now looking at the records one has a truck issue, one didnt, but the third that still runs did have that issue.
* Factory installed low ohm capcitor installed between the two brushes. I remember back at that time instructions saying they had to be there to clean the current from the electrical noise created by the motor. Now adays it is said dont do that it is done in the decoders. That shouldn't be an issue since all three pieces (Dcc system, decoder, and loco) are of the same age from the early 2000's. Plus the boards would have been smoked.
*Years of good running before two quit.
*A potential issue with motor brushes.
Seams like the issues most likely arent in the boards. Lots of bench testing. The idea of this post is to see if there might be hidden issues with these early dcc design frames, or early boards.
Thanks
Wolfie
I have found with my system, an NCE Powercab, that if you don’t clear out the consist, the locomotives when placed on the track individually dont respond. The horn, bell, and sounds may work, but there is no motor control or lighting. Clear out your consist when done running. If that isn’t the case, try putting them on straight DC. Pictures of the insides of the locos would help...
So, here is what we know. The OP has 3 Atlas GP units, all hardwired for DCC, all running in a consist. Two years ago, one GP quit running. Very recently, the second GP stopped running. Took the third GP out of the consist and reset it, but no response. No signs of electrical problems, no smoke, no burnt smell, nothing.
Here is what we don't know.
We need more information.
Rich
Alton Junction
Two Three questions for you...
Even a small short can wreck havoc with a decoder. I'd give the decoders a good look over.
Tom
https://tstage9.wixsite.com/nyc-modeling
Time...It marches on...without ever turning around to see if anyone is even keeping in step.
DCC controller?
Decoders?I have a couple Atlas but with sound on board.
If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.
I have 3 Altlas GP units from the erly runs back in 2003-05 somewhere. I had to hardwire in DCC. 2 years ago one quit running, that one had sound. Today the second one quit under identical situation. this one doesnt have sound. They had been running for a while, then just stopped dead. No signs like it had electrical contact problems. no noise. Just shut down. I cleared the consist and reset it. Thinking it might be a communication issue. No response. keep in mind the other unit (the third one in that order) was responding. I took it out of consist and again no response. identical to the other unit. no burning, blue smoke of death, or visible burnout. What are a list of potential problems fitting this situation I could target as a starting point?
Thanks Wolfie