donkey said:isn't the wire under the seats a pressure sender to detect if someone is sitting on them - and then in conjunction with the seatbelt sensor works out if it needs to beep at you?
no, that little gem is the wire that connects to the seat belt clamp.
This wire has like an electrical connector on the end but nothing to connect to - very strange. you need to actually looking under the seat to see it - i'll take a pic when it's light and post it!