Tachmeter malfunction ?

[axolotl98]

My Yams 115 Mod 91 tachometer seems to malfunction.
While the motor is operating, the rev meter displays zero, while all the rest info on the display seems to be complete.
For reasons unknown, after a couple of minutes it wakes up, and displays correctly the revs...
Any ideas on that ?

The LCD instrument is the 6Y5-83500-03-00 LCD-TACH-TRIM-OIL

[rodbolt17]

look in your manual, follow the dark green tach lead from the tach back to the engine.
I cant remember on that old a model if the CDI or the rectifier generates the tach signal.

[axolotl98]

Thanks, will do and will update. Will clean any connections I find.