Don't go disconnecting any alarm wire until you know for ding dang sure what's causing the fault. I agree, sounds like a low alarm warning. I'd consult the manual and determing what the beep represents and go from there. A solid alarm on my old 2 stroke 200 merc meant more than one thing, once of which was low oil. And don't rule out water pressure either. Just because it's spitting water, it might be slightly below tollerance. When's the last time you rebuilt the water pump?

And in the future, if you get an alarm on the water from an undetermined source, head in. It'd be a heck of a thing to ruin a motor because you assumed the alarm was false.

Wannabe...