Originally Posted by RichieST

Remove the centre belt and the latch. If it isn't there it can't be tested. Of course then replace it with a good working unit ASAP.

As for the alignment, they should really have been aligned as part of an MOT, unless of course there is another reason that they won't align, maybe due to incorrectly seated bulbs or whatever. They should however have told you why they couldn't adjust them.