Know anything about the alternator sense cable?

[MowatGTI]

Yo!

Been looking through my Haynes manual this avo as im changing the belt tonight.  When looking at the alternator yesterday, I noticed a cable dangling down not plugged into anything.  There is a place where it looks to plug into on the forward face on the alternator.  Haynes describes it as a sense cable.

Does anyone know what it does?  Also, does the fact that my one is disconnected mean anything?

I've not got a scooby doo.

Oh, its a '94 16v if that helps.

[Rmachines]

one is a sence cable and there is a Tacho signal plug as well,  I think that brings the warning light on if its unpluged... or at least it should do.   im wondering if your alternator has a dodgy regulator mabey and they have unpluged it to stop the light coming on at tick over im not sure.