took boat out today...ran fine for 45 mins....sat at dock got back in fired up and warning buzzer beeped twice...the beeps twice every 45 or so seconds...... drive oil was fine temp was fine oil press was fine..........what else does that system monitor?

anyone?

You will need to put a scan tool on it to determine. These motors are loaded with sensors....it could be several things. I have had that condition twice. Once was a bad oil pressure sending unit. Second time was a bad IAC valve.

I had the MAP sensor triggering my alarm. It's underneath the plastic motor cover. I unplugged it, plugged it back in and it never happened again.

Like Maklin said, get it scanned. I bought this software. It has a lot more features than a regular scan tool and cost about the same.

http://216.230.203.183/marine/marine.htm

It was money well spent. It tells you more than you need to know.

Those engines will beep when a code has been logged, and there are alot. A sensor out of perameters, a shift switch, etc. Hook it up to the computer to find out.

Being a kind of 496 expert. I would suggest that all 496 buyers in all boats petetion Mercury Marine to provide right along with the warranty manuals and such a $400 scan tool with every engine package sold. I know alot of Merc Dealers would scream foul, but hell there are just to many Merc 496 engine owners out there with buzzer codes who could save a lot of time and effort if they could just read the trouble codes and check the simple things before they are forced to a dealer for sometimes inconsequential service and charges. Whata you guys think?, another $400 ain't gona break any boat deal. Lets put this forum to good use and have this forum put a little needed pressure on money bags Merc!

Ray @ Raylar

Ray @ Raylar

i like that idea

Raylar is correct, everyone that has a 496 should have a scan tool. Another thing to consider is the PCM 555 service manual. These items will save allot of grief in the long run.

Ray, that makes TOO much sense! I'm thankful we have a Merc certified mechanic in our boat club. The fact he keeps his boat at my marina is even better.

are these newer 496's??? i just had a similar problem and with some in a 2005 boat, turned out to be the water pressure sensor that plugs directly into the top of the seawater pump (impeller housing). might be worth a look, would be a cheap fix. would be worth mentioning i had the same alarm as you.....2 beeps about 45 sec apart.