electric headrest not working on p38

Hi the front passenger head rest on my 1998 4.6 p38 does not extend up when the button is operated.it hasnt worked since i bought the car but being a fussy bugger i like everything to work ( this could be a ongoing prodject as i have found out owning a landy ) when the button is pushed the headrest just makes a clicking noise and will not come up..has anybody had this problem or know how to fix it,or should i just leave it alone.
kind regards
jake

Neither of mine have ever worked - they both do the same thing.

I think there is a cable drive and the cable gets damaged/stripped but it's about the least important of the faults on mine so have never got round to investigating it but I'd be interested in more information if you find out any. It was a job I was saving for when I do the heating elements, which are also not very high on my list of priorities!

Guy