2000 500 EFIs with 220 hours. Never had any problems with them (knock on wood), however yesterday on startup I had the alarms going off on starboard motor. Shut down both motors and restarted, alarms sounded again. Oil pressure was there and normal, my gauges don't ready water pressure at idle but the engines were pumping water, etc. Shut down motors and restarted one by one and no alarms. I looked at the drive fluid levels and they are close to the "low" line. Is this enough to trigger an alarm? It did the same thing later in the day, and after a few key on and off cycles it was fine and never sounded going down the river. Any ideas?

On my Donzi if the drive oil is low it will sound the alarm, i would fill that up first to see if it stops

same here .. alittle low and alarms go off. add fluid and see what happens.

Probably the drive lube sender was stuck.

float in drive oil bottle stuck on bottom. pull bottle drain and clean out careful not to break plastic barbed fitting were the hose hooks up.

just pull the code and you will know for sure what caused it.

the alarm circut is seperate from the 500efi computer,no code

Alarms on the 500efi's only sound for low drive lube, low oil psi and high water temp.

Was the alarm a constant alarm, or a series of beeps? On one of my 500EFI's the alarm would sound with an intermittent beep, (beep, beep, beep, pause for a few seconds, beep, beep, beep, pause ...) but only when the engine was above 3000 rpm. It was not one of the constant "holy chit" alarms, but it was working through the "buzzer" alarm system. Digging through the diagnostics manual we found that the knock sensor kicks in above 3000 rpm. We chased this "ghost" for over a year. The engine did not alarm until the rpm's got to, or over 3000 rpm. You could shut the engine off, restart and run with no alarm at idle, or up to ~2800 rpm. The it would go into an alarm mode. ECM never stored the code, either. Change the knock sensor and the alarm went away ... strange.