As the title says....we have a Kato SD40-2 into which we installed a Digitrax w/sound decoder and two speakers. After the decoder dying last year (and Digitrax switching it out for us) we reinstalled everything and all was great for a few months. Summer comes and goes and my son's little league is far more important than trains. 6 months later we clean the garage, clean all the track, vacuum off all the table and get back into train mode. Now, after sitting, our NCE power cab showed a short when we tried running this loco. We bought a new loco and it works fine around the entire track, so I would think that it is the Kato. I pull the shell and put the short detector (9 volt with clips and buzzer) across each of the power hookups on the top of the decoder (probably calling them the wrong thing) and it buzzed. I unsoldered each of the 4 power wires (we did the conversion to the wires instead of the copper strips that the Kato's have). Each pair of power wires have no short but the decoder still shows a short when I hook the detector to it. 1) I assume that it should not be doing this? 2) Should I keep digging to find a cause or is it most likely the decoder? If I should keep digging, where should I check next? 3) Is it a common thing for Digitrax to be this unreliable (if it is the decoder) since this would be two on one engine? If so, what is better? Thank you so much for your help and input!!!!!!! Frustrating as heck for my 12 yr old boy to have to wait as long as he did to get the thing running last year, only to have it for a few months and then have it down AGAIN as soon as we try setting it up again. Any help and/or suggestions would be GREATLY appreciated! Thank You!! Stew
next level of diagnosis: unsoldered the two brass strips which power the motor. The ones which go through the holes on the decoder. Now BOTH the decoder (going to the two posts that pick up power from the trucks) AND the motor (two brass strips which run down to the motor) show shorts. what direction do I go NOW!?!?! Help!!!!!
called Kato tested engine in DC on a test piece of track, ran great completely removed the decoder. still shows a short while sitting all on it's own on the bench. asked Kato about a better decoder. May be opening myself up to 8 million opinions here.....but...... he recommended ESU with Loksound. He said that it is more durable and the sound is good. I can't see getting the decoder replaced AGAIN from Digitrax and going through this again after less than 20 hours of use. Still looking for thoughts and suggestions! Thanks guys!! Stew
Wondering what scale locomotive are we working with here. From what you describe I would guess this is N scale?
If you're still getting a short when on DC, the frame halves are touching somehow. Check the continuity between the frame halves.
sorry woodone...HO. Usually I have been in the HO section. Didn't even think to start with that. gatrhumpy, the engine ran when on straight DC. Thank you for the suggestion on that though!!! When you attach the short detector to the decoder, all by itself sitting out on the workbench, it shows a short when I connect each of the input lugs (where the power would come in from the track). Starting to consign myself to the fact that this brand of decoder just isn't cutting it.
What kind of short detector are you using? I see that you said it was a buzzer with a battery, Right? Sometimes there is enough feed back in the decoder to make the detector buzz when you check to red to black. This is what I would do. If you have one, test the decoder with a decoder tester. Don't have one. Hook up a motor( a spare one) to the orange and gray wires and your DCC system to the red and black and see if you can control the motor. If OK, now you know that you have a problem in the loco to the decoder some place. Keep looking, you will find it! BTW what decoder are you using? Also did not Kato make two runs of this locomotive? The original and a mid production run. Would help to know which on you are working on.
