Hi got a mate who has a 1600 focus. He said he will get init in morn n within 5 mins the fan is on hot or cold. Hes had the thermo stat changed n still the same.
Anybody got any ideas on what this could be? Cant be much can it as fan circuit is very simple?? Cheers

 

I had the same on a diesel one, I was having problems with the egr.i plugged a code reader in no eml on, and reset the codes and the fan worked normally, then after a while the fan would run constant,code read it again and it was egr again.
Also might be worth checking aircon system if it has it

 

if it has air con and the heater is on the demist front window on the dial, the fan will come on automatically regardless if a/c on or not. Try moving it to feet and fan should go off