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5.7 MPI missing audio warning buzzer

I

iaff284

Contributing Member
Hey All,

I have a 2002 Four Winns 240H with a 350 Mag MPI engine. We have owned the boat for a year and a half now and it just dawned on me the other day that there has never been an audio warning buzzer sound when I turn the key on. I crawled under the dash and looked all over through the wiring and I cannot find the buzzer. So I looked through Merc Manual 24 to see what wires connect to the buzzer and it shows a Tan/Blu wire that should connect to the buzzer. I check every wire under the dash and no Tan/Blu wire. I go back to the cannon plug where the manual shows the Tan/Blu connecting in the #4 position and its not present on the gauge side of the cannon plug. In fact there are only 8 wires exiting the dash side of the cannon plug. Is it possible that this was an option?
 
On my 5.7L carbed MERC, the buzzer is in the wiring harness and is located on the engine block itself, not at the helm. As I recall, its aft on port. No mounting bracket, just a small "dangle". There is a wire that goes to a #6 (or #8) threaded grounding stud in the area, if that wire is disconnected ( sometimes intentionally), then no alarm.
 
Does yours go through the cannon plug? The other boat I had it was located under the dash. I was suprised to not see the tan/blu wire not coming the the plug towards the dash.
 
No.... Merc has been steadily "cost accounting" all their products and dangling the alarm in the engine harness is the cheapest way they could find to supply an audible alarm. If you want the alarm at the dash you will have to disconnect the present alarm and extend two wires to the dash. Then you will have the issue of how to mount it, as on mine at least, no mounting feature.
 
I will have to check and see if it is back there. I ground out the tan wire from the temp switch and got no audibles. I don't think there is one even hooked up.
 
Check both sides of the harness.....Its likely to be in the engine side and based on your description is missing on the 'boat' side. In your case, this was done by the riggers at Four Winns. I'd bet they grabbed a Mercruiser harness, never checked the part number, and slapped it in.....the engine fired up and they never thought about it again....

If you have the buzzer and wanna make it work, you'll have to supply the missing wire(s). Follow the Factory Manual and you should be good. Ideally you can add it to the back of the connector...
 
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