My son caused me to dig up my old 12V LEGO trains. Surprisingly they mostly work, except for one part - Electric, Train 12V Remote Control Switch Motor 4 x 8 x 1 2/3:

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This is the motor that drives the switches and railway crossings. I have 2 broken ones (and 2 working ones). One of them vibrates and buzzes a little but does not flip. The other one is completely dead and the ohmmeter gives a broken connection.

Does anyone have anything that might me help fix them? Photos about how to open them, etc...

  • I doubt getting in there will be very easy, but I'd start on the vibrating one. My 4.5V Technic motors of similar vintage spin over but are very easily stalled. I suspect the bearings need at least a good clean, possibly light grease but it depends on the details when you get inside
    – Chris H
    Commented Apr 13, 2021 at 12:00

1 Answer 1


Just repaired one...


Pry it open by using a precision knife on the lip of the bottom, using care to not damage the case:

opening the case

Inside you'll find a coil of copper wire. Check that the ends of the wire are properly soldered to the terminals, and re-solder if needed.

Interior view showing copper wire coil

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