Just a few weeks ago, i started to have a special effect when trying to switch TW560 off using the main switch for the controller: it would not react immediately, but slightly later.
it was just a minor inconvenience and i meant to write the usual TWIKE-suspects an email regarding their ideas, what could provoke this delay, soon.
as always, life is hectic and since dreifels’ controller has an ultra-low consumption sleep mode, which deactivates itself after a definable period of time, i didn’t feel too concerned, when for the first time, i was no longer able to turn off TW560 at all anymore.
thinking about where the problem might come from, the fact that interestingly enough, starting TW560 was never an issue, might indicate some more complicated problem than i would like to hope for.
this is where this blog entry gets interesting: delving into TW560’s innards:
we first remove the upper central console using a flat tool.
then we have a look at the pcb behind the panel… we can see the modifications made to accomodate the complete switch-off of the TWIKE (which even nowadays is done with a physical switch on non-dreifels controller TWIKEs – forget to completely switch off your TWIKE and leave on a few weeks’ vacation and your precious lithium batteries will have a damaging deep discharge cycle waiting for them – not a problem with a dreifels controller, however: every shutdown disconnects the batteries from the rest of the vehicle)
after some probing, luckily, the problem was found quickly: a hairline crack just where the metal bridge from the switch connects to the pcb. no surprise there, since the switch is subjected to some force when used and when in motion.
it seems that the slight rise in temperature during operation was enough to make the switch inoperable at the end of a trip and never at the beginning when starting TW560.
the solution is as easy as the issue: i soldered a flexible cable to bridge in order to avoid having the same problem sometime in the future.
i’m happy to report that with this repair, TW560 starts and stops operating normally again.