Re: 1980 evinrude75 hp, eldocraft, control alarm
If you are talking about the horn in the control box, it is temp indicator, when the engine overheats the horn goes off.
On the top of the cylinder head there is a temp sender with a single brown wire. Slide the rubber boot off of the connection, with the key in the on position, ground the connection to the block and the horn should sound. That is the sound you will here when the engine overheats.
