Engine alarm buzzer question

[joeybobo]

Hi all. I have a 2000 Mercruiser 5.7L EFI. After the two warning beeps go off and the engine is started, I am getting a low hum from the alarm buzzer, maybe at 1/8th the volume of the normal warning beeps. During normal operation engine temp is 170, oil pressure is fine, and gear lube is topped off.

I was wondering how loud the alarm is when it goes off. Do you think there's an issue, or is the buzzer just bad?

Thanks in advance!

 

[Don S]

Re: Engine alarm buzzer question

It will be as loud as the two beeps when it goes off.

If you just turn the ign. sw. to run and don't start the engine, do you still get the low hum?

 

[joeybobo]

Re: Engine alarm buzzer question

It will be as loud as the two beeps when it goes off.

If you just turn the ign. sw. to run and don't start the engine, do you still get the low hum?

Yeah, it's still on without the engine running.

 

[Don S]

Re: Engine alarm buzzer question

Disconnect the tan/blue wire from the buzzer and see if it still hums with the ign. sw. on and not running.

What is the serial number of your engine?

 

[joeybobo]

Re: Engine alarm buzzer question

Disconnect the tan/blue wire from the buzzer and see if it still hums with the ign. sw. on and not running.

What is the serial number of your engine?

I will check on that this afternoon. My serial number is 0L651960

 

[Don S]

Re: Engine alarm buzzer question

Here is some more information you may need.
View attachment 5.7 MEFI3.pdf

Go to page one of the above, and check connector 18 on the engine. Good chance you may find corrosion, or moisture in that connector.

 

[joeybobo]

Re: Engine alarm buzzer question

Got a new buzzer off of eBay and installed it today, hum is gone and buzzer test sound is ok.

Thanks for the helpful hints Don!