DRL: Now you have it, now you don't...

[Ciaopec]

was the turn signal on, or the flashers? I see some yellow down by the fog lights. Many DRL's turn off when one of the turn signals is on.

NB: The DRLs do not turn off when the turn signals are activated unlike most other cars on the road.

 

[Ciaopec]

While I could not find this it may be covered in another thread. If your DRLs do not work in "auto" or "on" or "parking" there is most likely something wrong with the hardware. If the DRLs are fading; hardware. If they do not come on during daylight hours with the slider in auto: check your "range mode" slider as DRLs are one of the things cut back to extend range (e.g. DRLs, reduced a/c-heat).
Hope this helps.

 

[Del Schier]

Definitely not a software issue but a problem with the headlights. I had my driver's side turn yellow on the inboard edge. With 57K my S is out of warranty and Tesla would not do me any favors, just offered me a new headlight for $1500. I replaced it myself with a new, broken lower tab, one from eBay for $150 shipped. The new one is perfect but now noticeably whiter than the original drivers side. I don't think the DRL's are LED, I think they are florescent and go bad in the same way.

 

[FlatSix911]

This is a well-known hardware issue... see this thread

Late 2016 / Early 2017 S Owners: How Are Your Daytime Running Lights Holding Up?