how do i get to?

I hope one of you can help, Last week getting out of the car I dropped my tom-tom, the cigar/wire connector still fitted, I think it must have dropped on the wire part of the unit because I can not get it to except a charge unless I hold and pull the wire in a particular way and then it charges and will work OK, Let go of the wire and the plug moves and it stops charging.
So how do I take it apart and get to the charging connector please. malc