Ford Mustang Owner's Manual page 86

Fog Lamps (If equipped)
The fog lamps switch is located on the console
to the left of the parking brake. The fog lamps
act as a supplement to the low beam headlamps
under limited visibility conditions such as rain,
snow, dust or fog and operate only when the
low beam headlamps are on.
Fog lamp switch
To turn the fog lamps on, push the concave
side of the rocker switch. An indicator light
will glow when the lamps are on.
To turn off, push the raised side of the
switch.
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