tach issue

[synergy]

I have a 2013 GL2274. my tach gauge fluctuate readings. The rpm sounds nor the speed on the motor does not change. How do I test??? Is it the gauge, wiring, or in the motor.

 

[Rssuttle]

I have a 2013 GL2274. my tach gauge fluctuate readings. The rpm sounds nor the speed on the motor does not change. How do I test??? Is it the gauge, wiring, or in the motor.

I’m not electronically inclined but I found this. Hope it helpshttps://goneoutdoors.com/test-tachometer-signal-boat-7901792.html