Practically Classics Forum

before I strip the dashboard.... the hot air worked fine, I had some resistance on the heater temp control, pushed throuhgh and now all i get is cold air.... not cool in November! any thoughts, i stripped a mk2 at the local yard (took ages to find such an old car, just modern tat in there!) but it was electric and i am told mine has a cable? thoughts appreciated!

Not familiar with the Mondeo, but temperature is either controlled by a water valve or by flaps which regulate the flow of air over the heater matrix. Suggest that you feel the pipes into and out of the heater and see whether both are hot at normal running temperature. It sounds as though something has seized

If it is the same as the MK1 focus then there are 2 cables that run from the knob to the heater itself. The cables have a habit of coming off the tracks inside the "bit that attaches to the knob".
Sorry if that's a bit vague.
My focus is 15 years old and i have had to replace cables twice in that time, most recently last month.

Cold engine.

Remove expansion bottle cap.
Disconnect a heater hose.
Connect garden hose to heater hose and flush 30 mins
Reverse the connection and then back flush.

Most cars now are air blended and have no water valve. Often the heater circuit on air blended cars is also the pump by pass and the volume of water in the heater circuit also helps cool the engine.

On both water blended and air blended systems if the engine starts to get hot then running the heater helps cool it down. The effect on some vehicles quite marked.
If a heater doesn't heat it could mean no water. Also on hot days turning the heater on briefly will confirm weather if the system has coolant or not. I often do this with my car.

Some cars with aircon have both flaps and and a water valve. The water valve is usually on or off only and a flap is used for temp control. My car is like this. GM system.

Bob.

TerryG wrote:If it is the same as the MK1 focus then there are 2 cables that run from the knob to the heater itself. The cables have a habit of coming off the tracks inside the "bit that attaches to the knob".
Sorry if that's a bit vague.
My focus is 15 years old and i have had to replace cables twice in that time, most recently last month.

Thanks for the advice buddy, just had a looksie in my garage and new cable needed the car came with an aftermarket stereo, looks like could have bent things.... naturally though the modneo's at my local scrappy yard are all mk2s so have eleci heaters..... cheers guys for the help and advice!