It's a 2003 Fiesta - the dial for the settings for screen, feet etc doesn't work although it will 'click' into place on each setting. The blower and heater work OK, but whatever setting is used incl. 'off', it always blows out onto your feet only. Nothing will come through the windscreen vents but will come through the interior heat vents OK.

Anybody got a clue where I can begin to trace what's wrong with it?