1991 Mercury 90HP
Tack will not work things checked so far
Have power to tach
have good ground
took out tach put in friends boat works perfect
put his tach in my boat does not work.
Have continuity from grey wire from motor to back of tach
Battery is charging great so I am guessing rectifier is good
boat runs and idles perfect
I see the grey wire goes into a square moduale Dont know how to test that piece whatever it is.
Any suggestions?
Tack will not work things checked so far
Have power to tach
have good ground
took out tach put in friends boat works perfect
put his tach in my boat does not work.
Have continuity from grey wire from motor to back of tach
Battery is charging great so I am guessing rectifier is good
boat runs and idles perfect
I see the grey wire goes into a square moduale Dont know how to test that piece whatever it is.
Any suggestions?
