The rotary heater control knob is stuck on cold and I think the cable may be stuck somewhere, how can I get to it without taking the whole dash to pieces?

Alan Fish, November 2008

I have an L reg espace with a heater that only works on full power. Took it to the garage who unplugged the leads under the bonnet and the fan worked on all settings temporarily. It looks as though the problem is in the contacts in one of the plugs in the power supply to the fan.
Havent found a solution to rectify permanently yet, though

PhilH, December 2008