Hopefully this will be informative and helpful;
First point is that (as described in the excellent Kia US tech pages at
GDS
The vehicle electrical circuits are actually a form of LAN.
Reading the manual in-depth revealed a paragraph that faults in the lighting circuits trigger a fail-safe "get home" setting of some headlights coming on.
Well, it's even cleverer than this - a fault in the airconditioning sensor module triggered the headlights to come on as a fault indicator. The flickering of the lights at idle is actually deliberate modulation of the lights by the vehicle electronics to prompt the owner to take the car into the garage to have it seen to.
Why this can't just be flagged up on a dashboard inidcator of "take car to garage" hasn't yet been explained.
So - all we need now is for them to find a part number for the aircon sensor and all should be well
cheers