‘Automatic headlights’ don’t work in fog?

[u/clynchy97]

About 40-50% of the cars we passed on the road today had no headlights on or only had the dim side lights. Do automatic lights not work in fog for these modern cars? Seems super sketchy

[u/stevekuehltruhe]

Nope. They work with a brightness sensor. Technically speaking it's "bright enough" in the fog so they don't activate.

I think for some premium cars they work in conjunction with other sensors and maybe even GPS/weather data.

Edit: But what I really find annoying is that the dtrl only light up the front LEDs and not the rear lights. I feel like that would be the bare minimum for this case.

[u/curiousredder → u/stevekuehltruhe]

I feel that the issue is that DRL are often so bright that a driver can believe they have their "lights" on (and in some cases i've seen the dashboard backlighting on too, reinforcing this belief).

DRL's should include rear lights too, or should be present only when fully functioning auto-lighting is also present.

[u/elislider → u/curiousredder]

Its a 2 part problem that car manufacturers could solve but apparently don't understand how (I mean cmon, GM is still making cars that the reverse lights are also used as parking/marker lights, so nobody behind you in a parking lot can tell if you're backing up, or just parked idly). but in the vast majority of cases, its because the gauge backlights are on regardless of whether the headlights are on. The 2nd part of the problem is cars that dont have a setting for "headlights always on when the car is on, and off when the car is off", instead most cars only have the settings for "headlights on" (meaning you'd have to remember to shut it off every time you turn the car off) and "auto sensing on" (which is better than nothing but depending on the car's auto sensing can result in no headlights during daytime)