I can finally reveal some research I've been involved with over the past year or so.
We (@redford, @mrtick and I) have reverse engineered the PLC code of NEWAG Impuls EMUs. These trains were locking up for arbitrary reasons after being serviced at third-party workshops. The manufacturer argued that this was because of malpractice by these workshops, and that they should be serviced by them instead of third parties.
1/4
We found that the PLC code actually contained logic that would lock up the train with bogus error codes after some date, or if the train wasn't running for a given time. One version of the controller actually contained GPS coordinates to contain the behaviour to third party workshops.
It was also possible to unlock the trains by pressing a key combination in the cabin controls. None of this was documented.
2/4
The key unlock was deleted in newer PLC software versions, but the lock logic remained.
After a certain update by NEWAG, the cabin controls would also display scary messages about copyright violations if the HMI detected a subset of conditions that should've engaged the lock but the train was still operational.
The trains also had a GSM telemetry unit that was broadcasting lock conditions, and in some cases appeared to be able to lock the train remotely.
3/4
@redford and @mrtick held an unrecorded talk a bout this at OhMyHack in Warsaw - I unfortunately couldn't make it because of Munich snow.
For now this is making the rounds in Polish-speaking sources, but we do have a talk scheduled about this at 37C3, in which we plan to do a deep dive into this and actually publish our findings.
@zaufanatrzeciastrona 's article about this: https://zaufanatrzeciastrona.pl/post/o-trzech-takich-co-zhakowali-prawdziwy-pociag-a-nawet-30-pociagow/
@q3k @redford @mrtick @zaufanatrzeciastrona
Is that a hack... or something put in place by company or its contractors?
Your post said 3rd party? Is that to mean they were using cheaper service providers?
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I can only imagine what riders experienced.
@mral @outie @JohnJBurnsIII @q3k
Hold yer horses there buckaroo.
Don't try to threaten me with the one GOOD outcome scenario...
@mral @outie @JohnJBurnsIII @q3k
Such a method as proposed is frankly stupid since it only punishes after the fact and preventing speeding is the desirable goal. A mandatory geo-gated speed limiter on all motor vehicles would be much more efficient and effective solution. But if fines after the fact are all that are on offer, then yes. Give it to me.
But not for you, of course. You are special and deserve to be treated as such. I think you should be given lights and a siren.
q3k 
John Burns
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