Loco has stopped running - sound is fine.

[LesXRN]

This week I decided to service a few loco's, after which, whilst on the rollers, my Princess Elizabeth slowly ground to a halt and now won't turn a wheel. The sound still works but that's it.

I'll have a look at the weekend but does anyone have any tips as to what may have occured please?

Just to clarify, it's Zimo fitted and loco drive.

Cheers. Les.

Mod edit: title amended to make issue searchable.

[What About The Bee]

Hello Les

Divide and conquer.

Remove and replace.

Trial various scenarios, testing for the faulty component.

Example: is the decoder bad? Replace the existing decoder with a known good decoder. Does the problem vanish?

Example: is the motor done? Lift the motor from the chassis and command motion. Does the motor spin?

Example: is the mechanism binding, preventing motor rotation? With the motor out, try moving the wheels. Do the wheels rotate freely?

In any of these scenarios, power the motor only for the briefest of time, so as to prevent damage to the coils.

There are many tests to perform. Put on your troubleshooting hat! Good luck!

Bee

[Rallymatt]

This might not be what you want to hear but…..

I bought an expensive sound fitted (Zimo decoder) Roco TT:120 locomotive. It was fabulous until it wasn’t (3 weeks) Same symptoms as you report. Sound but no movement. The motor control element of the decoder has failed, it’s been returned to Roco in Austria so I just have to wait now (3 weeks and counting) expensive decoders are no guarantee of reliability.

In your case can you test the voltage to the motor?

[LesXRN]

Thanks for the replies chaps.

I'll have a go at the suggestions and let you know.

As for the decoder, it's new, so if it's goosed I'll have a chat with Digitrains as I've bought quite a few from them this year.

As for the servicing, I wouldn't have thought that oiling the motion and axles would cause this problem. I did use the correct oil in a syringe type tool just to clarify.

Fingers crossed.

[Brew Man]

Depends how much oil you used. The mantra with oil is, if you can see it, you've used too much. Good luck with the fault finding.

[ColinB]

If it is a loco with the decoder in the tender check that the 4 pin plug that connects the loco to tender is pushed fully home. Also check that there are no loose wires on the plug. The two centre ones are the motor control. Most of my sound decoders when they die take out the sound first so I would be surprised if it is the decoder, but I suppose it does happen. Of course it could be a duff motor which is very possible. Try it on DC or another DCC decoder.

[LesXRN]

As promised, an update for you all.

DC worked fine, so I removed the Zimo and fitted an old Hornby sound decoder, it worked perfectly. So, it is the Zimo that has gone haywire.

I've spoken to Digitrains and it is covered as it's only a month old. Result.

[RB51]

Good to know you got it solved. Thanks for the update. R-

[LesXRN]

Another update after the plot thickened.

John at Digitrains tried the decoder that I returned and it worked fine.

Oddly enough, my other Princess with the same model of decoder also started behaving the same as the other one. So, I decided to try a different controller, an older Digitrax one, which proved that the loco worked as it should.

I then decided to go through all of the function buttons on my newer Digitrax controller, the only one lit was number 1 for sound. After pressing them on and off one at a time, the problem disappeared. It was either 7 or 9 that was causing the issue, I can't recall which, so that was a bit odd but at least it cured the problem.

Anyway, all's sorted and it remains a mystery as to why the problem arose.

Cheers. Les.