Kato GS-4 Dead

[Teditor]

I know there was a problem with the early Kato GS-4 with shorting out, but I believe there is another problem, mine reads the decoder OK the lights are working but there is no movement, is this a common problem.
Ted (Teditor) Freeman

[peteski]

No, not a common problem (at least to me).  But if you can access the decoder, I wouldn't call it "dead" Maybe sick, but not dead yet. 
Is this model new to you, or you owned it and it worked in the past?
Since you mentioned decoder, what brand/model decoder is it?  Is the headlight wired to the decoder? If yes, can you control it (on and off)?

[bman]

While I have zero steam locomotives, it sounds like you are not getting power to the locomotive's motor. I've had motor tabs not make good contact with the underside of some decoders on some of my diesels. The lights worked and the decoder would read, but no movement.

[JMaurer1]

The GS-4 mostly used Kato's own decoder: EM-13 (maybe I'm wrong, but other than the ECU and Zimo sound decoders, I don't know of anyone who makes a drop in decoder for the GS-4). It's located in the tender and has several sprung wipers that transfer power to the motor (see Spookshows website for a photo:  http://www.spookshow.net/loco/katogs4.html). The wipers go on top of the decoder and transfer motor power to the drawbar 'wires' to power the motor. I suspect the problem lies here. The circuit board in the engine is only there to power the lights in the engine. I would start there and make sure there's no corrosion on the contacts and that everything is in its proper place (those tabs can be tricky). You can also use a voltmeter to verify that power is coming out of the decoder which would then direct you to a problem with the motor.

[Sdynamo]

If the loco uses the Kato EM-13 "factory" DCC decoder, that decoder only handles motor control.  The lights (headlight, mars) get power directly from the track and have a separate board inside the boiler.



You can pop off the tender shell and see the decoder.  The brass tabs on the underside of the decoder pickup track power, and the brass tabs on top of the decoder ride under the small pickup "arms" that connect to the drawbar.  These arms bring power to the motor.

If the decoder does not look fried, make sure the small arms/wires for the drawbar are still in the correct position. Photos from Spookshow.

[peteski]

What's a bit puzzling to me is that if that decoder is used, but the motor doesn't run, how can CVs be read or written on programming track? There is a need for the motor to be connected for generating the acknowledgment pulse for the command station to know the decoder responded.

I actually I missed the fact that the headlights are working.  If the lights work then I wonder if another decoder (just for the lights) is installed in the locomotive itself.

[djconway]

Does the decoder support Train and Independent brakes with F6 and F7?

It would be really nice if manufacturers supplied a list of what functions are enabled by default, with the loco.  You pay $200+ for a loco you should get a printout of the decoder specs..

[peteski]

Does the decoder support Train and Independent brakes with F6 and F7?

We don't even know at this point what decoder is installed, so how can we talk about the specific functions?  Besides, what does the independent brake has to do with non running model?  Os this one of the famous Railwore Off-topic diversions?

If it is EM-13 then it is a Kato decoder made by Digitrax. Probably similar to DZ-125 or such.  But Zimo also makes a decoder that has same outline as EM-13. There is documentation for that decoder available at Zimo.  But it could also be one of many possible decoders hardwired inside the loco.  Ted didn't let that info slip out yet. 

[djconway]

We don't even know at this point what decoder is installed, so how can we talk about the specific functions?  Besides, what does the independent brake has to do with non running model?  Os this one of the famous Railwore Off-topic diversions?

If it is EM-13 then it is a Kato decoder made by Digitrax. Probably similar to DZ-125 or such.  But Zimo also makes a decoder that has same outline as EM-13. There is documentation for that decoder available at Zimo.  But it could also be one of many possible decoders hardwired inside the loco.  Ted didn't let that info slip out yet. 

Is it truly not running?
I belong to a round robin group that several members have enabled brake functions on their decoders.  It really confuses users in that you have to set the brake(s) to stop a train or release the brake(s) to get it moving again.  I don't know what typoe of decoders they are using but it adds a layer of realism to the operations.

[peteski]

Is it truly not running?
I belong to a round robin group that several members have enabled brake functions on their decoders.  It really confuses users in that you have to set the brake(s) to stop a train or release the brake(s) to get it moving again.  I don't know what typoe of decoders they are using but it adds a layer of realism to the operations.

Again, all those helpful ideas are shots in the dark without knowing what decoder is in that model.  The features you mentioned are usually present in the higher end decoders (like Tsunami, ESU or Zimo). Digitrax or NCE does not have those features.