The near side rear central locking mechanism on my 1999 166 2.5 24V has
stopped working. Has anyone experienced this kind of thing before and
if so do have any suggestions on where to look or what to replace?
The mechanism appears to be incorporated into the main door lock which
appears to be a sealed unit. Should I replace this or could the cause
be elsewhere, in which case any recommendations of where to get such
spare parts in the UK or on the web?

Many thanks

Jon