Re: Seatbelt stuck - help!
I had this problem in my 147...
...unfortunately just before an MOT was due shortly!
After taking the rear seats and seat belt mechanism apart, I learnt the hard way on how they operate!
There is a locking rod between the 2 seats and if this does not engage i.e. slide across correctly then the seatbelt will not feed any belt. Sometimes by simpy reseating the rear seats and locking them into position can allow the slider lock to engage. If this does not happen, then you may need to realign them by loosening the bolts that hold the rear seats in place - found by flipping the cushions and boot lining up.
Mine still plays up at times and the quick way to sort it is a hard knock from a hammer on the seat mounts just before the bolts, so that the seats marginally move or the knock may be shaking the slider lock into place...
It's quite a frustrating problem but glad now I know how they work.