There is a well-known manual for repairing a speedometer with replacing a capacitor. But after repairing my own and several others, I discovered that in fact the problem is not in the capacitor, but in the pins with which the small additional boards are attached to the main board:
https://www.youtube.com/watch?v=oOqNdMhogJU&feature
All speedometers I have seen have had this problem. The soldering on these pins just cracks over time. It would seem that you can simply renew the solder. But the problem is that the boards are made using a very strange technology with deposition of a conductive layer on a ceramic substrate. And after cracking off the spraying, there is simply nowhere to solder. After suffering with the restoration of a couple of pieces, I decided to just make the boards from scratch.
Here's the result:
And here are the gerber files and lists of components, with which you can order the manufacture of boards:
https://drive.google.com/drive/folde...t2?usp=sharing
Most of the components can be simply rearranged from the old board, but there are also spray-applied resistors. They will have to be bought new.