Sensor hooked to tach gauge?

[Sgt_allen2006]

I have a 1994 Johnson 225 Ocean Runner out boat, I recently started to replace my old gauges. There is a sensor hooked to my old tach gauge with the numbers 176360"OS" 13 CID_BA I have been ablt to determine where the grey and blue wires connects to, I am however unable to figure out where the purple wires connects. If anyone know the answer to this any help would be greatly appreciated. Also what is the sensor for???????

 

[Dhadley]

Re: Sensor hooked to tach gauge?

The purple wire is key on 12 volts, basically the wire that supplies 12 volts when the key is turned on.

 

[Sgt_allen2006]

Re: Sensor hooked to tach gauge?

so the purple wire hooks to the ignition??