loose wires 90 HP Mercury 3 cylinder

[fsds123]

I replaced the oil reservoir tank and noticed 3 loose wires. Motor is new to me as of a year ago and runs fine. Anyone have any idea what they are for?

 

[Texasmark]

Yeah. Tan is OT sense wire. If you ground that wire the horn will sound if the key is on.

OT sensor is embedded in the water jacket plate on the rear of the block, about mid way down on the left side...to the left of spark plug #2. Possibly the sensor failed (shorted) and the PO just disconnected it.

 

[fsds123]

What is an OT sensor? And should the tan wire be plugged in to the brown and white wire?

 

[racerone]

OT= overtemperature---- sensor I think.