SOLVED: it was the ignition switch. Wiggled it around and they started working again.

Hello. I just recently bought a volvo 850, and found out that the headlights, turn signals, and brake lights only work occasionally and seemingly at random. Sometimes they all work, and sometimes none of them do, but never anything in between, either on or off. The hazards switch always works though. Today I was messing around turning the lights on and off to try and find the issue, when there was a strange wirring buzzing noise from the radio area, that only happened when the lights were turned on. I turned the hazards on and the whirring happened every time it blinked. I turned the car off and tried to replicate it and I haven’t heard it since.

has anyone experienced anything like this, or know what this could be?

 

Welcome to the world of 850's, Grayson. I put your symptoms into my favorite AI search, and it provided a lot of suggestions (many of which do not seem to be applicable to you). One of its suggestions involved fuses, but that would not be intermittent, so take what they say with a grain of salt. Perhaps you can start with something like an AI search. The buzzing sounds like it could be a relay, but I don't know of one in the radio area. The radio is very easy to remove; try taking it out and checking for the noise. Perhaps you can pinpoint it more closely.

Good luck. I wouldn't be surprised if it's something simple.