Tach connection for Johnson 2005 90 HP

[bronx68]

I am trying to troubleshoot a tach problem. Where on the engine can I measure the tach signal? Also the tach is a combo engine check device (several wires enter the tach) on this boat. Which wire is the tach signal on this connector at the tach?

 

[john j]

I have 99 70 hp johnson the gray wire is the tach lead going into the back of tach check your engine service manual .

 

[john j]

Under my dash there is a purple and a black and a gray wire to test with hanging in wireing harness it purple is the power supply black is the ground gray is the pulse engine .

 

[joereeves]

The "gray" wire is the sensor lead. What kind of problem are you having?

 

[KRAKEN]

I also have just acquired a twin rig Johnson 140hp 4 st, 2004 set up and both tachos do not work. the engine test lights work just the tachos don't.
previous owner may have disconnected something to stop reading engine hours perhaps.
also starboard engine tilt gauge is not working.

Plus if Grey wire is pulse wire how do you test for signal