Multiple times in the past I've had this issue where the low beam(s) do not work. My car has the quad headlamps. The problem has always been fixed by simply replacing the relay module of the respective side. I'll add that in the mean time, my work around is to turn on the high beams, but disconnect the inner high beam bulbs. Since the issue is always the same, the low beams do not come on by simply turning on the switch to on, but for some reason if I turn on the high beams, all four work, so that tells me the bulbs are fine, and the issue is the relay module.
I've had many different relay modules installed, only differing by a a couple watts and the part number. To my understanding, I should have DBC 3265. Which both front rellay modules are 3265 this time the issue came up again but it did not resolve the problem. Same exact thing, I turn on my lights and nothing turns on but the parking lights, if I turn on the high beams all four work. So I use my workaround to have lights. The issue is usually one side, not both like this time. My local mechanic suggested it was the actual switch inside the car not working properly and went out to buy one. I replaced it and problem still persists. I have a third relay module that I tried to be sure it wasn't those installed with issues.
Is there another module I'm not aware of causing this? Or what else can I do to troubleshoot it and find the source?

 

I know this is old post, but did you find a fix for this issue? I’m having the same problem