thunderbolt 5 igniton sensor

[cooter2506]

I just picked up my new sensor and it has 3 wires. I know where the two striped ones go but other is a black wire with a ring terminal on it. Im assuming it is a ground but we all know what assuming is. So does it just go to a good ground? replacement is a Sierra 18-5116-1 . Mercruiser 5.0 1998

 

[JustJason]

Re: thunderbolt 5 igniton sensor

that'd be a hall effect pickup for a TB4 ignitions system.....
never seen one with a black wire one it.
Sierra... in all their infinite wisdom.... must have an explanation for it

 

[xltier]

Re: thunderbolt 5 igniton sensor

i just installed one from sierra and it had the black wire.i put it to ground.boat runs great now.