VW Golf - when do these side lamps turn on?

Question

My 2015 VW Golf has the fancy lighting system with the pointable HID headlights (I leave it off; it really distracts me when the light beam doesn't point where the car's going). For quite a while I've had an "Error: Adaptive Front Lighting (AFS)" warning pop up, but the headlights seem fine (and still do their usual wiggle when I start the car).

I finally did some googling, and apparently this indicates a bulb problem, probably with one of these side-illumination light bulbs:

Clearly these are supposed to light up when turning, and it makes sense that one could be out and I wouldn't notice. I have no problem with how the lights are currently functioning, but I do want that error message to go away, and would be willing to replace a bulb or two to make it do so. But, here's the problem: neither of these lights EVER seems to turn on (at least while parked with engine running and headlights on). I've turned the wheel all the way, turned on the turn signals: nothing. I'd rather not blindly replace bulbs, hoping to get the right one.

So, finally: the question. Under what circumstances are those two lights supposed to light up?

Final Edit: I pulled the two bulbs, and found that the left cornering bulb had failed (the right bulb was good, even though it never turned on). I've replaced the failed bulb (it's a standard H7 halogen); the error message has gone away, and now both bulbs work. See my answer below for the details.

#MyLastVolkswagen

(and no, this isn't the only reason...)

Answer 1

Had the same error. Replaced the lights and error went away

Those are "cornering" lights

They get turned on at night, when you put it in reverse (both will turn on)

Or when you're going around a corner under 50km/h (my personal observation, could be different) with turn signal turned on

Answer 2

As Ruslan said, and as I suspected, these are indeed cornering lamps. They are turned on if any of the following are true:

• The turn signals are turned on (the lamp on the same side will be lit),
• The steering wheel is turned more than about 120° to one side (the lamp on the side you're turning towards will be lit), or
• The gear shift is put into reverse (both lamps will be lit).

The following requirements apply:

• The engine must be running,
• The full headlights must be on (not just parking lights),
• The car must not be moving faster than about 25MPH, and
• Both cornering bulbs must be good (see below).

The following doesn't matter:

• The parking brake can be on or off,
• The shift (automatic) can be in any gear, even park (except it must be in reverse to light both cornering lamps),
• The car doesn't have to be moving, and
• It doesn't have to be night.

The "both cornering bulbs must be good" requirement was what was confusing me. One of my cornering bulbs was dead, but for some reason the car responds by disabling both bulbs. This, of course, is stupid; it makes it twice as hard to figure out which bulb is out, and deprives me of the benefit (if any) of the working cornering bulb.