Kato GS-4 - DCC problems with factory ESU LokSound

[ryan_wilkerson]

Just purchased a used Kato GS-4 SP #4449 with LokSound (part #126-0307-LS). Looking at Trovestar https://www.trovestar.com/generic/zoom.php?id=190257 it says it was released in Dec 2021 so I was hoping it wouldn't have any DCC operational issues but unfortunately it does.

I'm not an expert at these so I'm hoping the TRW brain trust can offer some advice to help me out.

Symptoms:
1) When I use my NCE PowerCab to read the decoder, it says "cannot read".
2) The lights stay on constant when the locomotive is set on the track and will not turn off using the DCC controller.
3) The address is 4449. When changing from speed step 0 to 1, it goes from stop to full speed and can't be slowed down except by setting to zero again.
4) Amazingly the sound works (bell, whistle, etc)

Ideas to try?

If this is something simple, I'll fix and keep it so I don't have to return it. The seller said it was tested and worked. Maybe he just tested the sound?

Thank you in advance.

-Ryan

[tehachapifan]

I'm going to have to ponder much of this some more, but the headlight and Mars light staying on is normal with the Kato GS-4. They used a lightboard that takes its power straight off track power and cannot be controlled with a DCC controller. So, you can strike that one off the list as a sign of a problem.

I'm inclined to think a decoder reset is in order. Do you happen to have a LokProgrammer? One isn't necessary for a reset, but I think it makes it a little easier.

[ryan_wilkerson]

Thanks for the info on the lighting, I didn't know that about the GS-4. Very different from other locomotives.

I actually do have a LokProgrammer, I'll try to fire that up and see what it says.

[peteski]

Thanks for the info on the lighting, I didn't know that about the GS-4. Very different from other locomotives.

That is because connecting the front LEDs to the decoder woudl reqire rather extensive modifications. As it is now all they had to was to remove the dummy DC board in the tender and slide in ESU 58731 LokSound 5 micro DCC Direct Kato Japan decoder and drop in the speaker

[tehachapifan]

Glad to hear you have a LokProgrammer!

One thing that might be worth trying to start things off is disabling "analog mode" in the "analog settings" section.

While I haven't personally experienced any issues with analog being enabled while on DCC, I seem to recall some anecdotal accounts of similar behavior to what you describe with other DCC locos.

I think those accounts described the loco taking off like a rocket when track power was applied (versus when increasing speed steps above 0), but it's worth a shot.

Also, while you are in the Lok Programmer, take a look at the "motor settings" page and see if it the speed table set up in a speed curve or the 3 values of VStart, VMid and VHigh.

If it is set up with the VStart, VMid and VHigh option, see what CV's 2, 5 and 6 are set at on the manual CV input page.

Additionally, depending on how long ago you purchased your LokProgrammer or updated the software, you may need to do an update prior to proceeding (I believe you need LokProgrammer 5 for this loco).

[ryan_wilkerson]

I reset it twice (CV8=8...maybe the first time didn't take?) and it seems to have cleared up the "full speed ahead" issue and now it can be read by the NCE PowerCab and also the LokProgrammer.
You guys are the best!

One issue that I didn't notice before is that the motor is quite loud when running (audible without the sound on). Is that normal?
It doesn't sound like a mechanical whine, more like an electrical motor control issue (speed step one, it's louder than any other locomotive I have). Ideas?

[tehachapifan]

Glad to hear a reset helped!

Regarding the new motor noise, it could be a BEMF setting issue.

As a test, try going to the Motor Settings page and uncheck the "enable load control/back EMF" box and see what happens. The loco may not start moving right away and might be jerky, but this test is to see what happens with this noise.

If the noise improved or changed, there are adjustments to motor settings that can be done that may help.

[peteski]

Ryan, since before reset you only ran the loco at full speed, now after the reset does the motor sound different at full speed?  Or you just noticing the motor noise because you can run it at slower speeds?

In the motor settings section  there is also a Motor PMW frequency setting on the bottom of that window.  Change it to the other setting and see if it makes a difference.  It might not make a difference, but worth a try.