Can anyone tell me what this connection is for? Found by battery at side of fuses but cant see where it has came from?!?!?!?

The other half of it should be under the grey engine fuse box.

Thats what i thought and ive looked under there and cant see anything at all?!?!?!? Car is running fine might i add, i only noticed cos i disconnected batt to clean map sensor and saw it dangling there?!?!?!?

This is the connector! Only 4 wires going to it?!?!?!

I think it's only used for cars that have cruise control.
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