Help identifying wire on engine

[Rohan]

Attached is a photo of the back side of my engine, a Yanmar 3YM30 29hp diesel. I was working on the exhaust and noticed a plug for some kind of wiring hanging down on the back of the engine block. The red arrow is pointing to it.

It must not be crucial, since I've owned this boat for 2 years and it's been running fine. But I am curious what it is. The owner's manual for the engine doesn't mention anything about it. Anyone have any ideas?

[Emmalina]

Looks like the wire that goes to the water sensor when you have a sail drive fitted. not used when you have a shaft drive !

[Rohan]

Originally Posted by Emmalina

Looks like the wire that goes to the water sensor when you have a sail drive fitted. not used when you have a shaft drive !

Thank you. I do have a shaft drive, so that makes sense!