Instruments fails

[Jokern]

On a 250 Yamaha 2008 mod. the instruments dies sometime when its sunny.
On a cold and rainy day it works fine.
Its a "bus" system with a red cable from the engine to a connectionblock witch the instruments connect to.
I have 12 V from the battery on this block.

Any tips on whats wrong?

[boats.net]

Take it to your dealer, if it's a bad meter Yamaha will probably warranty it.