"WHITE-OPTIC" or "SELECTIVE YELLOW" are permissible front fog color. 99% of new-market vehicles are equipped with white-optic variety and in nearly all cases are installed in the lower front bumper apron.
AUS made Fords have typically used a YELLOW telltale (pilot light) with that ISO symbol for front fog lights, whilst the rest of the world team uses GREEN for front fogs-on, and YELLOW for rear fog-on, instead.
Reason why this is so; some dumbarse Aussie working at Hella-AUS made it so citing no ADR/UNECE requirement as to lamp-pilot-light-function color, forgetting ISO sets this, duh.
NB - A pilot-light/telltale is mandatory for the rear fog circuit, is optional for front fog and aftermarket driving lamp installs, but again is mandatory for a cars regular high-beams.
Front fogs per ADR are wired to allow operation when a cars headlight switch is on park, low or high-beam. The premium position is to have the headlight switch on 'park' (ie sidelights), and the front fogs on. Does a couple of things for safety; 1. reduces 'reflected glare' in heavy fog et al conditions caused even by low-beam headlights; 2. allows the front indicators to stand out more clearly to other traffic because they are then not masked by the cars regular low-beam.
FURTHER (lamp identification) - The lamp IS a front fog lamp IF it bears on the lens, typically near the "E-mark" (the letter 'E' and a number next to it in a circle, eg; E13), the designation "02B" or "B". The letter B is relevant here and represents ADR/UNECE "front fog lamp compliance".
Now, a 'driving lamp' bears the designation "HR", eg; HR-P means the lamp is a "halogen driving lamp bearing a plastic lens". The letter "R" is relevant for a driving lamp.
A 'driving lamp' supplements a cars standardised high-beam performance, and in aftermarket installs *must* have its own independent switch, but can only operate if the cars regular high-beam switch is also activated.