Engine alarm at startup

Hi - I searched the archives and think I have a bit of a handle on this, appreciate any input.

I have a 2004 Yamaha F150TXR with about 275 hours on a Sailfish 218. Second owner, always well maintained. At startup yesterday as I turned the key to "ON", the alarm sounded. As I turned the key to "START", the starter engaged, but the engine didn't turn over. To be honest, I didn't notice the alarm the first time, since the engine always turns over on first try. I checked the obvious kill-switch lanyard and tried again - no luck. Removed cowling, checked oil - OK. Out of gas? Gauges say no. Water in fuel - filter looks OK. Closed everything up - went away - grabbed a couple gallons of fuel so I don't have a "d'oh!" moment. Put fuel in - turned key to ON (no alarms) and starts first try. Go to fuel dock and add a cushion. Starts again no problem. Go out for a quick 45 minutes of fishing with engine off drifting - afterwards go to start up engine - whoops - alarm. Seeking to avoid Sea Tow, try everything just done - open gas cap & close, raise/lower engine, remove/engage kill switch lanyard, hey engine starts. Back at the dock when safely tied up & engine off, tried for kicks to start engine - nope, alarm. Raise/lower engine, engine starts.

So my question is - does the alarm come on in the "ON" position for any other reason than kill switch? Note that the alarm does not come on when underway.

Thanks in advance for thoughts!

Re: Engine alarm at startup

unplug the water detect lead and retry.
its the blue connecter at the fuel cup.
other than that low voltage will trigger an alarm.
what guage package is it rigged with ?
this engine doesnt self test the alarm at key on, the water detect will only sound an audible if the shift is in nuetral.

Re: Engine alarm at startup

Thanks Rodbolt. I will check the water detect lead. I don't know which gauges the boat has - they are analog but I'm not sure they're Yamaha OEM (from memory - I don't think they have the engine oil/temp lights). I will check that as well. I was also going to change out the kill switch in case it was corroded and grounding erroneously.

One question - I have the Racor fuel filter/water separator & it looked clean (but I will recheck and drain off). I've heard the Yamaha is very sensitive to water and we run E10 here. If disconnecting the lead solves the problem, should I just run with it off? Our season is winding down here in the NE so there's only a couple more weeks & I'll be winterizing incl changing filters, etc. Thanks again for your help!