Puzzled - three locos won't work!

[Torper]

I have six locos (five kit built, one RTR) all equipped with Zimo decoders.  Until today all have worked well.  Over the last few days I have been carrying out some work on my trackwork during which time five of these locos were standing on the layout. Today, when I started everything up again, I found that three of the locos don't work.  The two others work perfectly, and the sixth, which had not been on the layout, also works fine.

 

The three that don't work appear to be getting power because they give the occasional very slight movement when power is applied.  On the programming track, using both "1 STD" and "2 CV" I get the message through my NCE handset "Can not read CV"  on all three.

 

I can only think that the decoders have been damaged in some way, possibly because they were on the layout while I was working on the track and for some of that time power was on, though I can't recall any major short circuits and that would also not explain why the other two locos are apparently unharmed.  Before I send the decoders off for repair under Zimo's excellent repair system, I wonder if anyone has any ideas for a simpler solution?

 

DT

[Judge Dread]

Have you tried reprogramming them?

[cravensdmufan]

I had a similar problem with a Bachmann decoder.

 

Managed to recover it by using NCE Powercab option 7 on the program track (see page 54 in the System Reference Manual).

.

It resets the decoder to it's original factory settings.  But after doing that I still had to set the start voltage (CV2) manually.  Worked fine.

 

You don't say if your Zimo decoders are sound ones - mine was a bog standard Bachmann one.  I don't think I'd risk doing a reset on a sound one!

[Stevelewis]

Simply  reset  the  decoders  to  factory  settings  and  re  try  them,  if  this  fails  try  the  decoders  in differnt  locos  if  this  is  feasible

[Torper]

As the loco is not recognised by the handset and as the message I get when I try to set a CV is "Can not read CV", I don't see how I can reset the decoder which, I believe, would normally by CV8 = 8.

 

DT

[Stevelewis]

I had a similar problem with a Bachmann decoder.

 

Managed to recover it by using NCE Powercab option 7 on the program track (see page 54 in the System Reference Manual).

.

It resets the decoder to it's original factory settings.  But after doing that I still had to set the start voltage (CV2) manually.  Worked fine.

 

You don't say if your Zimo decoders are sound ones - mine was a bog standard Bachmann one.  I don't think I'd risk doing a reset on a sound one!

 

There  is  no  problem usually  doing  a  factory  reset  on  Sound  decoders,  the  re  set   just  resets  the  running  not  the  sound,  I  have  set  many sound decoders  from  N  to  G scale  never  had  a problem  with  the  sound. 

[Lady_Ava_Hay]

You may do better if this topic was posted in DCC Sound, wherein lives Paul Chetter who is a total guru when it comes to Zimo decoders and sound ones in particular.

 

At a very basic level it sounds a bit that the controller is using a different protocol to read and change CV's. Not all CV's are capable of being changed on a mainline. You will need a programming track that is entirely separate and is usually connected to different terminals in any event. This is much safer anyway.

 

On the plus side I very much doubt that the decoder is damaged unless the magic blue smoke was set free. This would be evident when the decoder is inspected as any burnt components will be visible albeit with the aid of a magnifying glass.

 

The problem with returning to Zimo for repair is that this will almost certainly wipe the sound project completely.

[Tony_S]

As the loco is not recognised by the handset and as the message I get when I try to set a CV is "Can not read CV", I don't see how I can reset the decoder which, I believe, would normally by CV8 = 8.

 

DT

Put it on a programming track and write whatever reset value is appropriate for a Zimo decoder to cv8. Then try reading CV1, it should then be three. It doesn't matter if you can't read a cv before the reset.

[Torper]

Thanks everyone so far.

 

My handset deals fine with CVs on the locos that are still working.  It is not recognising those that aren't though it certainly used to.

I am using a programming track, and am attempting to program accordingly.

I shall remove one of the loco bodies and see if there is any sign (or smell) of damage to the decoder.  As I said earlier, I think the decoders are getting some message because there is some very slight movement when power is initially applied.

Only one of the decoders is a sound one.  I got them all from Digitrains who, in conjunction with Zimo, offer a fixed price (£15) turn-round decoder repair scheme.  Basically, on receipt of the damaged one and the fee they send out a new one and the old one is returned to Zimo and eventually put back into stock.  Digitrains would reinstall the sound file (which is one of theirs) at no extra cost.

 

DT

[cravensdmufan]

There  is  no  problem usually  doing  a  factory  reset  on  Sound  decoders,  the  re  set   just  resets  the  running  not  the  sound,  I  have  set  many sound decoders  from  N  to  G scale  never  had  a problem  with  the  sound. 

That's useful to know, thanks for that advice.

[Phil S]

Have you tried them on analogue or simply with a 9v battery!!    this will confirm the decoders still work (unless they are cv29 analogue disabled)

It is also NOT  a requirement that 'read-back' be enabled  ... i prefer not to use it, as it slows programminmg and is uneccessary - you know the new value you are giving it 8-)

[Torper]

Well, two of the locos are now working again.  One I managed to reset with CV 8=8 (wish I'd remembered to make a note of all the settings i had previously carefully worked out for it) and the other appears to have cured itself, although was a little intermittent at first.  It's now happily making use of my new rolling road.  The third however remains obstinately dead (it is a Caledonian loco).  I have known a previous case where a decoder that to all intents and purposes seemed dead recovered after 24 hours, so I'm hoping that that will be the case with this one - it may, albeit quicker, have been the case with the one that cured itself.

 

Phil, I know it's not a requirement that read back be enabled, but as a relative novice with DCC I find it very helpful indeed and wouldn't like to be without it.  I don't only like to know the new value, I also find it useful to know the old one.

 

DT

[Crewlisle]

Why not create your own spreadsheet in Excel whether you have 5 or 50 locos?.  This is the format I use to keep tabs on my locos.  The only CVs I normally adjust are CV1 to CV4.  For CV1 I try to use only the last two digits of the number even though I have 50 locos but no accessories operated via DCC.  Where I have to use a four digit address I add CV17 & 18 values in the column  ‘Decoder Fitting’.   In the same column (if changed from default) I also add CV5 & 6 values of speed curves or CV54 & 55 values if I have had to adjust the motor characteristics.  I use a separate spreadsheet for loco servicing records.

 

Peter

LOCO HISTORY + CV SETTINGS - FORMAT.xlsx

[Nigelcliffe]

One could do all Peter describes using JMRI and the decoder records it keeps - with or without JMRI actually connected to your DCC system. 

 

- Nigel

[Torper]

You are of course absolutely right, Peter.  I've never actually used a spreadsheet in my life, but I'm sure that a table in my word processing programme would do as well and I'll get on with it.

 

Nigel, I've never considered JMRI because the only computing device I have is a desktop which is some distance away from the railway and I feel that while not essential it would be desirable to have the computer close to the layout.  Also, I've felt that the sprog is expensive and unnecessary for my small layout. However, although my layout isn't growing the number of locos is, and I have also been given a laptop which, while old and underpowered for most of todays applications, might well be fine for JMRI and I shall investigate that further.  I have an NCE Powercab system and wonder if I would be better (and slightly cheaper) buying the NCE usb interface rather than a sprog.

 

Incidentally, the errant third loco is still not working and I shall take it to bits to see if there is a hardware problem.

 

DT

[Nigelcliffe]

Nigel, I've never considered JMRI because the only computing device I have is a desktop which is some distance away from the railway and I feel that while not essential it would be desirable to have the computer close to the layout.  Also, I've felt that the sprog is expensive and unnecessary for my small layout. However, although my layout isn't growing the number of locos is, and I have also been given a laptop which, while old and underpowered for most of todays applications, might well be fine for JMRI and I shall investigate that further.  I have an NCE Powercab system and wonder if I would be better (and slightly cheaper) buying the NCE usb interface rather than a sprog.

 

The Sprog and the NCE interface achieve slightly different things, and which is "best" depends on your planned use.   The NCE interface connects the NCE PowerCab to a computer, and thus the computer can do things which an NCE handset can do, including programming and running the layout.   The Sprog is a stand-alone device (rather than an interface to some other system), and as such provides a stand-alone computer controlled system. 

With the NCE option, I'd also get the NCE programming switch device, which goes on the output of the PowerCab and splits off a dedicated programming track from the mainline output - my thinking is that programming commands to the entire layout is a bad idea and bound to go wrong sooner or later. 

 

The old laptop is likely to be fine.   If running XP, I'd be very tempted to try a Linux version on it - Mint would be my starting place.  For a layout laptop running JMRI, Linux is likely to be less hassle than the growing list of issues around XP (and likely to get worse when Oracle upgrade Java to 1.9).    If its running Vista, probably try Linux.   Windows 7 or later, then I'd stick with Windows unless you want to be using Linux.   

[Torper]

I'm still not sure whether to get the sprog (I assume sprog 2 would be adequate) or the NCE unit.  I don't intend to run my layout by computer or (if I had one, which I don't) smartphone - all I want is an easy way to see, check, change and record the CVs and loco details.  A spreadsheet would of course do that but I have weakness for computery gadgets.....(I've just installed Linux Mint dual boot with Windows on the old laptop and it's working fine).  Basically, taking all that into account, is there anything the sprog will do that the NCE unit won't?

 

Incidentally, I've got that other loco working again - I basically stripped it down, checked the wiring, put it back together and then it worked.  However, a couple of days later I was impressed by the firebox glow and smoke effects, particularly as I hadn't installed either firebox or smoke units.  The loco managed quite a good flame under the cab before I switched it off.  More work on the wiring, and cleaning up some light oil I'd used to lubricate the gears, restored normality.  The decoder is in the tender and so was well away from these problems!

 

DT

[Nigelcliffe]

I'm still not sure whether to get the sprog (I assume sprog 2 would be adequate) or the NCE unit.  I don't intend to run my layout by computer or (if I had one, which I don't) smartphone - all I want is an easy way to see, check, change and record the CVs and loco details.  A spreadsheet would of course do that but I have weakness for computery gadgets.....(I've just installed Linux Mint dual boot with Windows on the old laptop and it's working fine).  Basically, taking all that into account, is there anything the sprog will do that the NCE unit won't?

 

 

Sprog 2 is fine for programming and test-running OO and smaller scales.  

 

The fundamental difference between Sprog and NCE interface is how they are used.   Sprog is stand-alone, so apart from a power supply and computer, it just does it.   NCE unit requires the PowerCab to be present.     For some people a portable test setup, or a workbench with Sprog is ideal for them.    For others, they always work next to their layout system, so being plugged into the NCE is ideal for them.     Decide on how you intend to use things.   

 

 

- Nigel