Hi I’ve just purchased a fiesta trend when I put the dipped headlights on the offside front fog lamp comes on when I turn the steering wheel to the left the near side fog comes on they don’t come on together is this right thank you.

This is correct, the car is using the fog lamps as cornering lamps so it lights up the road in the direction you are going. It only happens at slow speed. You may find that it also happens at slow speed when you indicate, so if you indicate right the right fog lamp will come on as you approach the corner. You may also find that both fog lamps come on automatically when you reverse, again to give more visibility. The normal operation of the fog lamps is not affected by this feature.

3 hours ago, Mosswood said:

Hi I’ve just purchased a fiesta trend when I put the dipped headlights on the offside front fog lamp comes on when I turn the steering wheel to the left the near side fog comes on they don’t come on together is this right thank you

As Paul has said that is how they are supposed to operate, so it's not a fault.

Interestingly enough operating only one fog light at a time contravenes a law from the late 1970's which made it illegal to fit only one front fog light to a vehicle (which was common at the time). The law says that if front fog lights are fitted that they must always be fitted and wired to operate in pairs. The same applies to driving lights.

Personally I don't like them and don't feel I find any benefit from having one fog light come on while going round a slight bend or corner. The good news is that you can easily turn this function off using FORScan, it takes less than ten minutes to do.

That law is overruled by EU type approval legislation which allows single fog lamp use under strict conditions. The system must be factory-fitted and will only operate up to a speed of 40km/hr when the normal headlamps are on. I actually find it quite useful, especially when reversing.

1 hour ago, Paulius55 said:

I actually find it quite useful, especially when reversing.

You find the front fog light useful when reversing !!!!

Not been picky but aren't you looking the wrong way ? 🤣

It just lights more up around me. I don't know about you but I look at the sides and back when reversing, although I mainly look at my screen as I have a camera.