tachometer stopped working

[vcs]

I have a 1988 Johnson 150 VRO. I replaced the tach with a new one, still not working. I have traced the grey signal wire back to the engine and used an ohm meter to check for continuity. Any suggestions would be greatly appreciated.
Tony

[doodlebug]

check to see if your charging system is working,if not you will need to ck resistance on voltage reg. and stator but
prob. voltage reg.