Again thanks for the help

The DCC chip is definitely the culprit after testing with another working DCC chip (from the class 58 that I managed to botch soldering on while trying to replace the motor - if anyone wants a bodyshell and bogies let me know!)

I don't want to fry another chip. In the attached image when I was gently pressing the loco to the track I got a low voltage shock from the metal block in "circle 3". Wonder if there is some frayed wiring that has shorted the chip, but i thought there were some built in protections against shorts with expensive chips like ESU Loko?

The chip clips just underneath the soundboard (? the large black board marked N20-PCB Rear) but there definitely is a hard soldered wire, not quite the one advised by Revolution. The brown wire runs from the main board of the chip (hard soldered) to the speaker (hard soldered).

I could probably hold my hands steady enough (with a couple of Glenmorangies) to solder that but am I a barking up the wrong tree/what replacement chip is now compatible given the age of the loco /should I just give up and send for repair - if so are Rapido the only reccomended option?

Again thanks to all for the patient replies and suggestions

Is this a stray wire strand or loose wire?

Quote from: ntpntpntp on July 21, 2025, 07:50:16 PMIs this a stray wire strand or loose wire?

Thanks for the input - I'm not sure the fault lies there. There are three red wired soldered connections to that PCB including the one in your blow up picture. I checked the working front driving car and it has the same set-up and the loco worked with a new DCC chip!

It's just a 6-pin interface. I assume that's what you've found?



You've a few options. The original sound project was done by Legomanbiffo - he still sells the sound project on 6-pin decoders here: https://www.dckits-devideos.co.uk/index.php?route=product/product&path=221_251_229&product_id=1409

It won't be the same decoder, as the Loksound V4 Micro they used is now obsolete. You'll need to email them to request a single replacement, as they sell as pairs by default. They're very responsive.

You could also get the decoder repaired, I forget who the current agent for ESU is, but that may only be £35 or so.

Or you could stick a pair of silent 6-pin decoders in, and not have sound. I'd do both power cars or you'll have a horrible mismatch.

The only soldered connections should be from the decoder to the speaker. No soldering needed on the decoder (or the PCB), so installation isn't quite as daunting as it may seem.

njee20

yes 6 pin interface

as always that is super helpful!!

much appreciated

And, FWIW, I've had the body off one of my sound equipped ones for the first time.
Mine also has a single blue wire not connected to anything by the decoder, like item 1 in your photos.

Regards,

John P

Yes, you can see it in mine too. It's the common return, because you could just chop the 6-pin plug off and hardwire it. The 6-pin plug uses one pin as a common return.

So - I've sent my Pendolino for repair to someone I thought was an expert with the model.

I'm not going to name them but they were, slow, expensive, & didn't respond to messages [in contrast I'd give a shout out to Hookstone Models who are the opposite with other sets I've had done even sending YouTube videos of the repair progress].

Traction tyres have been fitted and both DCC chips and the sound chip replaced and light bars fitted in all coaches.

Some woes remain if anyone can help!?

The two locos do not appear speed matched/one is much faster than the other which I think is a possible cause of frequent derailments. I'm running them through a Roco Z21.

I've tested running the full set of coaches with only one loco but still get derailments, so wondering how I should verify the positioning bogies and couplings. I don't know if this model is uniquely delicate and prone to derail but other long HST's (Kato/Eurostar whizz around the same curves/over the same points at considerably higher speeds without problem?

I've succesfully set up lighting and sound functions and originally all were working ok. Now, sounds like the horn only work when stationary. The coach lights also flicker a lot while doing a circuit (again other HST's with lighting don't do this and lighting "stays alive" all the way around, so I think I can rule out track feed problems).

Steps I've already taken without sucess

- I've followed the manual procedure for resetting the functions to factory default and reloading them into the Z21 app for the vehicle
- I've followed the manual procedure for increasing the volume of sound functions.


This is turning into a lot of frustrating time fixing niggle after niggle with an expensive product that should be close to being able to run straight out of the box! 

I can't help with the DCC issues and I don't have a pendolino.

But....I do have a Voyager and I was getting a derailing issue on points and curves with just one of the carriages.

On close examination the coupling was not swinging freely in its socket on one carriage.

If I picked the carriage up it was fine but on the track it would not swing.

There was a tiny burr of plastic where the coupling slides from side to side in the groove that holds it.
Sitting the carriage on the track applied just enough pressure to make the coupling catch.

Once I'd removed the burr everything was fine.

Cheers
Martin

I feel your pain. I recently got a Pendelino and have spent loads of hours already trying to get it to run adequately. I'm slowly making progress but still getting way too many derailments. It's all extremely frustrating. Feel like the traction tyres are to blame for a fair few issues. I would like to be able to pick up some non traction tyred wheels if possible.

I've also found the two motors to run at different speeds. I've speed matched as much as I can, but they seem to run faster forwards than backwards so they'll always be a mismatch when the train is coupled together.

I'll add checking the couplings for burrs to my list of things to try.

Thanks both @Hightower and @port perran

I also have a Voyager (two Voyagers in a consist) but they don't have these derailing issues constantly!

As a newbie I'm not sure what you both mean by "checking the couplings for burrs"?

I can see on straight/level track that all couplings appear to be aligned and because the Pendolino conducts through the couplings to the light bars in the coaches that there appears to be good conductivity. As soon as the train moves everyting changes - lights flicker and wheels misalign with track. To reiterate this does not happen with any other long HST that I have running on exactly the same layout.

It's also a royal (C II R) pain in the arse to even rail the Pendolino and coaches to start - I have Kato railing tracks and re-railing tracks around the circuit but there is always a problem with one of the coaches or the locos!

Problem 1 - get it speed matched
Problem 2  - get it stay on track
Problem 3 - get sounds working
Problem 4 - no enjoyment unless 1-3 solved!

Hi,

Just to add some balance here.

I have 4 original Pendo's with ESU sound decoders and 3 from the second batch which I have fitted with Zimo decoders.

All 7 of them run fine on my layout with no speed matching issues.

I use large radius Peco Code 55 Electrofrog points on my layout and I don't get de-railments.

I have to be careful in my fiddle yard as that has short radius points and sometimes they can be an issue.

As you are using a Z21, then as long as you are using the Z21 app you don't need to speed match the two driving cars. You can use the Traction feature for Locos in the App and time each one over a fixed length of track, then put them in a train together in the App and the Z21 will do the rest.

By the way, what make are the new DCC chips?

I don't know why you are having issues with the sounds, on my 4 sound equipped ones all the sounds work as expected.

Regards,

John P

Burrs are just little bits of excess plastic.
The sort of thing you have to file off when separating plastic kit parts from their sprues.

I firmly believe the traction tyres are a cause of issues on these. There's a small inbuilt mismatch in the power cars, but because of the traction tyres they have too much grip on the rail head, and so just derail at the slightest provocation. It's exactly as you describe. I didn't have this problem originally, but I then discovered my original sets had lost all their traction tyres! I did have more gentle curves when they were new, I suspect it's exacerbated on all but the gentlest curves, which may explain why @jpendle doesn't have problems on his garage empire.

I believe it can still happen with a single power car because it will still snatch if it loses pickup instanteously, should be much reduced though. Is it still problems with the power cars derailing, or the intermediate coaches?

I've actually just sent off the CAD to someone to see if they can machine wheels without traction tyre grooves. I will have spares if he can. I've actually replaced the traction tyre-fitted wheels with 3D printed ones, but they're not tough enough to supply.

As for your problems:

1) should be fairly straight forward - couple one coach to each power car and do this in the normal way
2) I don't have a silver bullet here, it seems to be a problem which is much more marked on DCC, short of "remove the traction tyres"
3) No idea what's going on there, what decoders are we talking? Which sound project?

Quote from: jpendle on October 09, 2025, 08:30:42 PMHi,

Just to add some balance here.

I have 4 original Pendo's with ESU sound decoders and 3 from the second batch which I have fitted with Zimo decoders.

All 7 of them run fine on my layout with no speed matching issues.

I use large radius Peco Code 55 Electrofrog points on my layout and I don't get de-railments.

I have to be careful in my fiddle yard as that has short radius points and sometimes they can be an issue.

As you are using a Z21, then as long as you are using the Z21 app you don't need to speed match the two driving cars. You can use the Traction feature for Locos in the App and time each one over a fixed length of track, then put them in a train together in the App and the Z21 will do the rest.

By the way, what make are the new DCC chips? I only know that the sound chip is ESU Loko

I don't know why you are having issues with the sounds, on my 4 sound equipped ones all the sounds work as expected.

Regards,

John P

Thanks for the input

It's difficult to detect what brand the replacement DCC chips are when the repairer doesn't supply any info and the chips themselves have no branding.

The repairer basically used as an excuse for delays and his charges the fact that I hadn't noticed there were no traction tyres.

Like others I feel these are the cause of poor pick ups and derailments but I'm not an internet keyboard warrior who can say that for 100% sure.

But my Pendo was from the very first production run and I'm not sure that they were ever meant to have traction tyres on that batch. I originally bought it for my son when he was too young to appreciate it and it's sat in a loft for years, so it's hardly ever been run and if there were traction tyres fitted originally it's really hard to see how they could have been worn off after 20 hours of running at most.

It's the locos with the traction tyres that derail the most. The coaches immediately adjacent to the locos also appear vulnerable to frequent derailment and the couplings between those and the loco appear ok but not much left to right travel in them. Occasionally also get derailments on centre coaches but think that is just a hazard of the hobby to be expected!

One thing I'm pondering - the light flickering might mean that the coaches haven't been put back together properly after light bar installation (?).  If they are gently pushed against the track, they pick up current and light up. When pressure released the lighting goes off or flickers. I'm obviously reluctant to use more force than is needed and damaging the model!

I have intermittent Kato re-railers around my circuit which work with every model apart from the Pendo. I have a 150/350/A4/TGV/Eurostar/Tomix Thomas & Percy/Class 58 & full wagon load/Voyager all of which rerail on circuits where there is a minor derailment- it has to be the most frustrating model I've ever had just to get it set up up on the track. So any tips on how to rail it correctly in the first place or any devices to help?