4 stroke yamaha 115hp RPM wiring

[BassAssassin2009]

I have a 115hp 4 stroke Yamaha and trying to hook up a 703 control box but the RPM gauge is not working. How do I hook up the rpm. I got the light to work but rpm stays at 1000. The harness on the motor is a 9 pin, but the harness from my control box are 10 pin. I talk to the shop and they say the 703 control box are compatible with my motor.

The harness has 3 pairs of the same color wires that are not hook up. I tried all of them and does not work.

 

[rodbolt]

Re: 4 stroke yamaha 115hp RPM wiring

the 703 box in a 10 pin version is compatible with every F115 ever built.
on the 703 you will see a 4 wire lead,yellow is key on power for the tach,red is constant 12V key on or off and may or may not be used on your application,black is tach ground and the dark green is tach send.
is this a factory Yamaha brand tach, if not are you sure the tach is 4 stroke compatible.

 

[BassAssassin2009]

Re: 4 stroke yamaha 115hp RPM wiring

So i found out that it was not the wiring and it was just a bad rpm gauge. It was stuck at 1000 rpm so I got an old yamaha gauge from a friend of mine and it worked. Thanks