2011 Tacoma DRL’s suddenly not working!!!

My issue is peculiar.

I recently uninstalled the previous owner’s 10 year old aftermarket head unit in place of an Apple CarPlay compatible head unit! It was an old Eclipse head unit, and was tied pretty well to the truck’s wiring (parking brake sensor, speed sensor, separate GPS antenna, etc). I removed as much of the old wiring as I could, and installed my new one. It works very well and I’m very happy with the upgrade.

QUESTION - I started my truck this morning and noticed my DRLs were not on, as they always are (duh). My hazards and blinkers both work as expected, it’s just the DRL “always on” function that suddenly isn’t working anymore. Also, my fog lights do not work anymore as well. What could cause this? Are there any wires in the head unit area that could cause these issues?

I’ve checked the 10A fuse labeled “tail” located inside the cab by the driver door. It’s fine. It’s just weird that the lights work normally when prompted by the blinkers/hazards, but not by themselves. Please help me!!

 

AH! Okay - I did a bit more sleuthing around other threads and I indeed "fixed" my DRL problem. For those who stumble across this thread in the future asking similar questions - the DRLs do *NOT* work while the e-brake is engaged. I don't know why this is. Taking off my e-brake solved the DRL issue.

Now for the fog lights. They still don't work. I haven't ran them in a long time. The bulbs both look fine, any ideas on testing the fog lights to determine the problem?

 

Fog lights only work when the headlights are on, the do not work with the DRL, parking lights or Hi-Beams, only the headlights, this is a DOT legality thing.

I'd make sure you're troubleshooting under those conditions if you haven't.

Otherwise there's the Fog light anytime mod which I have.

 

Ha - I feel like an idiot. Yes, my fog lights work with my headlights on. I’m sure more research would’ve eventually led me to that conclusion. So glad this forum exists. Thank you!!