EMERGENCIES – If the windscreen fogs up

If the windscreen fogs up

Setting off on a humid day, it’s a good idea to keep a piece of fabric handy.

To avoid fogging in wet weather, do not blow cold air into the cabin.

Close all windows.

Defogging (synonym: demisting) position of the controls:

1.         Air Intake – Outside Air, i.e. the rightmost position.

2.         Air Flow – Windscreen, i.e. the rightmost position.

3.         Fan Speed – High to clear, Low to maintain.

4.         Temperature Control – red zone, i.e. Warm.

5.         Rear Window Demister – on.

6.         Air Conditioning (A/C) – on.

Photo: Emergencies - Defogging position of air controls

Practically, defogging is achieved through heating up the windows, and can be run with the Air Conditioning off. Turning on the Air Conditioning is recommended for two reasons: first, it assists demisting through lowering humidity in the cabin, and second, it prevents air ducts from over-drying.

If the windscreen has not started defogging in 2 minutes, try switching the Temperature control to the blue zone, i.e. Cold, with Air Conditioning on.

For the heating elements to last long, switch the Rear Window Demister off soon after the rear window has cleared. In some car models the Rear Window Demister switches off automatically; in others you have to turn it off yourself.

After windows have cleared, turn the Fan Speed down to “Low”; a bit later you can switch heating off or half open a window, if you wish.