Hi guys. So I’ve got an early 2008 mk6 fiesta Zetec 1.25, I’ve owned this car for almost a year now. As of a couple weeks ago I had my fan on 4 blowing hot air out as I was driving. Randomly on that drive it just cut out and stopped working. A couple hours ago I replaced the blower heat resistor and that wasn’t the issue. Coolant isn’t an issue either as I read that could lead into it, no blown fuses to do with it, im really struggling to understand what is wrong with it and how I can fix it. It’s very annoying especially in this current weather because I freeze whenever I drive that car as it’s always cold, and I can never see out of my windscreen because of my de-mister. Please can someone help me ASAP, I’m losing my crap with this car.

I could be completely wrong but I have a similar thing happening with my 2018 Focus and when I brought it to the dealer they said it was a blown module due to too much current or volts. (The part has since been ordered)

If your positive that your fuses are all good (including mega fuses if your car has them) then this could be possible. 
 

Hopefully this is of some help as it seems to be similar enough as I spent a couple days diagnosing fuses when it happened to me.

I think the heater temperature is controlled by a little solenoid module that gets sticky and fails. It is not hard to change nor dear to buy if it is as I remember. I would expect some heat to come out whether the fan worked or not.  Have you cleaned the fan housing out?

Heater fan resistor only affects the slower fan speeds. Not the fastest fan speed. So if it stopped working on the fastest speed it wasn’t going to be due to the resistor pack.  Might be the fan is worn out or just needs a bit of fiddling with carbon brushes/ cleaning commutator.  I would get a voltmeter on the fan connections and see if power is getting to it.  I have no idea where the fan is or how easy it is to get to on that model.

Should really be in the fiesta forum, not general chat

Just now, isetta said:

Should really be in the fiesta forum, not general chat

You are 100% correct 👍

Just waiting to see if FOC admin delete the whole thread and all the answers 🤔

I have attached the Heating and Ventilation wiring diagram below:

If all else fails, you could always trace these wires and ensure they are getting the required current and you should find the issue fairly easily then