I have a problem with a Tsunami decoder TSU-750 in a Kato GS-4 (N scale) . This is a second run GS-4 numbered 4453. So It is DCC friendly ( per Kato). I installed the decoder and tested it, them programmed it on a test track, then ran it on a 80 foot main layout. Did about 1 lap in forward and 1 lap in reverse.
Packed the unit up and sent it back to my customer- I get a call a day or so latter with him saying the GS-4 moved about a foot and quit running- makes sounds but will not run. OK, send it back to me and I will see what is wrong. Get the GS-4 back and I can’t read the decoder, so out it comes and I sent it back to SoundTraxx for repair. In the mean time I look the locomotive over real close, I pushed on the rear drivers to see if the wheels would touch the frame any where. I checked the wheels to the frame with a OHM meter. I never was able to get a short between the wheels and the frame. So I have a spare non sound decoder, so I installed it in the locomotive just to see if motor would run. Yes, the motor was fine and I ran the locomotive around the layout several times. Never any problem.
I get the repaired (or new) decoder back from SoundTraxx. So I re install the sound decoder. I test ran again and programmed it again. Then I ran the unit for about 10 mimutes. Ran fine. so I let it set overnight, next day I run it again, forwards and backwards for about another 10 minuites, started and stopped and ran it though turnouts, the works. Ran fine. Next day before I packed it in a box I test ran it one more time- NO problems.
Shipped to back to the owner. Two days later he calls- the locomotive ran about 6 feet and stopped, make sounds but will not run. I ask him to put on a programming track and see if he can read back the decoder— NO. BTW he is using a NCE Power Cab for DCC control.
Does this person have more than just this one locomotive? Is he having trouble with the others or just the Kato? It sounds to me like his system is being overloaded and the circuit breaker is turning it off. May be poorly wired layout or a short in his wiring, or the wrong power supply being used.
It sounds to me like he is the one with the problem, not you.
I’ve had the exact same problem with a Kato GS4/TSU750 combo a while ago.Loco went well for a few laps then lost tractive power while sounds kept alive.I found the next to impossible thing with a Kato…the motor had a shorted spot that showed up only when loco was going very slow (actually creeping) forward.I replaced the motor and installed a regular decoder and all seems well,I will retry the TSU when budget allows getting it repaired.
Does it have traction tires, and is he trying to pull too much train on a grade so it stalls out? That non-replaceable fuse in the micro is such a silly idea, and for the size of it they ought to be able to do better with the allowed current - those thumbnail motor only decoder can do a full amp.
Very interesting, how in the world did you find that?
BTW, if the decoder is not that old, send it back for repair. You need a receipt and fill out the service repair form on there site. Sent it back before it gets too old. They might repair at N/C .
I’ve had this exact same problem - still haven’t found a solution. One thing I did notice when I was installing, though, is that the stiff copper wires carrying the current between tender and loco have a tendency to come out of place - they need to be touching the metal frame properly. I also noticed that the TSU-750 seems to heat up rapidly in the confines of the GS-4 tender shell - is it possible it could be overheating and shutting down?
The overheating and shutting down problem I have seen before. I mount the decoder to the weight which acts as a large heat sink. The thing about the overheating is when it cools the loco will run again after it has cooled. This one (while in the owners hands) has not run long enough to cause a overheating problem.
Back to yours shutting down, try using tub and tile caulking ( non silicone) to attach the decoder to the weight. I don’t know how you have your speaker and decoder put inside the tender but I have done several this way and I have not had a thermal shut down yet.
THIS one is a PITA so far. When I get it back to do for the third time, I will remove the motor and run wires from the motor to the decoder. No more wheel to frame issues. This is what I have done on first run GS-4’s in the past.