Really appreciate the reply. It sounds as if you are going to be correct in the diagnosis (much to my dismay of having to spend out a load more money). I took a look at the fuses; however, we are missing the detail on our list and are unable to pinpoint which fuse would control the pump for the central locking system. Are you able to help guide us to the correct fuse number?

Another problem has also arisen; the stereo (standard Becker model fitted with the Bose upgrade speaker package) still appears to fully function, however, with no sound. There is no way to turn the volume up or down as the switch does not appear to function at all. Could this be linked? Any help would be greatly appreciated.

Thanks in advance.