Well I'm due some brownie points
I just fixed the heater control in my wife's Focus. Some months ago she was coming home from college, started the car and tried to turn the heater control knob to the cool setting. The control knob was a bit stiff and as she tried to force it around, something gave with the result that the knob would no longer operate properly - we could get cold air but no hot at all. As its been summer I'd forgotten all about it until now so I thought I'd better get on with it before winter sets in. Anyway, the knobs are located immediately below the car's audio system so I got some removal keys and after a lot of fiddling around managed to remove the unit which allowed me to see, just, what was going on behind the heater control knob. It turns out that the knob operates a cable similar to a bicycle brake cable the end of which has a hoop which simply slips over a plastic spigot on the rear of the knob. Turning the knob pulls or pushes the cable which in turn presumably operates (at the other end) a valve or flap which either allows or prevents hot air to enter the car. Anyway, all that had happened is that the metal cable had bent slightly and this had caused it to slip off the back of the knob as it was turned. It was a 2 minute job just to straighten the cable very gently and re attach it. Result! She now has a car with heating in it again, just in time for the colder mornings/evenings...
A simple job but given that I have never been one for tinkering with cars etc. I'm very pleased with myself. Now all I need to concentrate on is getting my wife to be a bit gentler when handling knobs...