Yamaha F90 Faint alarm buzzer

[shoresls1]

Just got this boat and it runs fine, been out several times. The alarm buzzer was not working when tested by pulling the lanyard and cranking. I have the digital round yamaha gauges and see no flashing temp or anything odd. I pulled buzzer and applied power/ground to confirm it was bad. It was. I bought another buzzer(not yamaha)from the local boat store. I have used these in the past with no issue. Standard 2-wire piezo buzzer. Installed it and checked it by pulling lanyard, loud alarm. Lanyard back in and starts/runs normally no alarm. However, I noticed a faint alarm. Very faint. If the console door was closed I would not have heard it. It is constant with the key on, engine running or not.

ideas?

[DennisG01]

Is there another buzzer under there? For example, a depthfinder often has a buzzer used for a shallow or deep alarm. It should be loud, of course, but it either be failing or the wires/connections are corroded.

Verify where the sound is coming from, first.

Otherwise, sounds like you have some stray current getting to the buzzer.

[shoresls1]

It's the warning buzzer. I can cover the buzzer in my hand and it's almost silent. I unplug the buzzer and it's gone.

From my knowledge(meaning I don't know everything) yamaha uses ground to signal the alarm if an event occurs. In other words, the sensors get 12v when keyed ON but grounds to complete the circuit when a event occurs.
I would have a water in fuel sensor and water temp sensor. I have unplugged each and the faint alarm is still there. I would assume it's getting some stray/slight ground from somewhere. There are no indications on the gauge that an event is occurring.

[fairdeal]

However, I noticed a faint alarm. Very faint. If the console door was closed I would not have heard it. It is constant with the key on, engine running or not.

Otherwise, sounds like you have some stray current getting to the buzzer.

Well, the buzzer plugs into the yellow ("ignition") wire of the keyswitch -
so with key on,
it is directly connected to full power.

For current to flow through it, producing a sound,
there must also be a ground -
that's what the ECM provides, in an alarm state.

My only guess:

maybe, the "switching" state in the ECM: ground, or no ground,
is not absolutely "discrete" -
and the new aftermarket buzzer is more sensitive to a small "leakage" current.

[shoresls1]

I guess that may be a possibility.

[boscoe99]

It is the buzzer itself. The type. The design. Not compatible with the motor electrics.

Yamaha once had a problem with certain of their own buzzers that caused the same problem.
zbuz.jpg

[shoresls1]

Anyone know the part# for this new buzzer? local dealer wants $52 for it. Only # I come up with is #703-83383-11-00, she says that is for the 703 box.

[99yam40]

most electronic relays will not shut off all current like the mechanical relays did. so some leakage happens.
maybe Boscoe can come up with a part #

[boscoe99]

https://www.boats.net/search?q=90891-40793-00