Hi All .

Recently thee engine cooling fan has been coming on a lot even from a stone cold start and also noticed shes drinking a lot of fuel.
I'm aware of the aircon will come on depending on the position of the airflow etc.
Anyway a mechanic i know plugged his diagnostic box the on board computer reported a fault for AC which would explain the fan been on pretty constant and the engine running cooler and hence burning more fuel as it thinks its always cold.

His not sure at this stage if its a relay or may be an issue with the loom somewhere.

has anyone experienced this before on the focus or its a known issue perhaps?
Be grateful off any advise and hope the above makes sense.
Thank you tim

 

They could be different problems, a faulty CTS can cause this, which should have logged a fault etc, does it do it when the ignition is switched on?

I don't think the MK1 is advanced enough to report a fault on the A/C?

Martin

 

Hi thanks for the reply.

So possible the control switch in the dash might be the fault is that what you mean?

To be honest i have not tried with the ignition on i will try that however the fan does turn off as soon switch the engine off.

Tim.

 

What he means is that the engine temperature sender may be faulty causing the ECU to either;

Go into a safety mode by firing up the fan all the time

or

The possibly faulty sender is fooling the ECU into thinking the engine is hot/cold when it is not.


Note that on the Focus there is not a coolant temp sender. There is a temperature sender that sits in a blind hole in the head that means the head (metal) temperature.

As above though, I don't think it likely to be an A/C issue but more likely to be the temp sender in the head.