Spent the better half of the morning chasing down diagnostic trouble codes. Left for work this morning at 06:00 and everything seemed fine. I got about 10 minutes away from the house and a check engine light popped up on the dash. Within seconds, my headlights went out. Signature lights, low beams, high beams, markers, blinkers, everything.... I also noticed that my AC started to blow warm shortly thereafter. Knowing that warm air can often relate to increased engine operating temps, decided to check the coolant temp and it was at 251F. I pulled my scanner to check codes and found numerous DTCs for the headlamps and also PCM P0480-00 for a cooling fan control circuit malfunction.
Long story short, it was a poor connection at the N08 high current fuse located at the fuse block under the hood. N08 goes to the radiator fan. It didn't feel super loose, but it also didn't take much effort to break free with a ratcheting wrench. I wiped down the contact area, reinstalled, and then double checked a few other fuses and relays while I was in there just to make sure there weren't any "smoking guns" that jumped out as problem areas.
I'm running Retroshop's LED adapter harnesses for my OEM LED headlight conversion and per their instructions, one of the wires is installed at the N08 fuse. I installed these lights a couple years ago so it took me a few minutes to retrace my steps, but once I remembered that, it immediately explained why the headlights also went offline at the exact same time. Everything appears to be working just fine now (knocking on wood) but will drop an update if anything changes.
