Problematic Headlights and Turn signal On 99 Buick

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MODEL:Century Custom
MILES:Unknown, approx 180000
DESCRIBE ISSUE....... The headlight and turn signals on the front of this vehicle has always been a huge headache. And from talking to other people and seeing these cars from the same time frame driving towards me while I'm out running around, seems it's a problem for most owners of these cars as there is always a bulb out or turn signal that doesn't work 9 out of 10 times. And now the headlights are totally out. No high or low beams at all. I went through the fuses and they look fine. I even for the heck of it went through and put new in just in case with anything that had to do with headlight, turn signals, and power. But still nothing. It's highly unlikely that all bulbs went out at the same time, low and high, 4 bulbs. Anyone have any ideas on this? Or maybe something I am missing perhaps?
I used the test light and checked the fuses. They were good. I tested the connector coming from the harness and checked each lead and they have power coming to them. All except one on both the left and right that did not light up. Is it because it was the ground? I'm terrible at electrical on cars. I did notice also that the parking lights do work. One is very dim though. I did not check the actual bulb sockets though as the main wire was plugged into the headlight assembly, but i'll check that tomorrow.


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NOT a Buick, but I'd like to mention an ordeal I went through on a Subaru. That's right, and Import. Anyhow, what I learned was that unlike "the old days" this car had switching in BOTH the Power AND the Ground circuits. This cleverness allowed them to manage not just Off/On/High/Low, but Daytime Running, Auto Off, and Fog Lights.
Knowing zip about this Buick, other than cars seem more and more to be more and more plastic, I'd figure out how the Turn Signals are supposed to be Grounded, and run a new ground wire to some solid metal nearby. You could try that with the headlights, too, but if the Buick is cleverly wired like the Suby was, you might find you had lights you couldn't turn off.
Thank you for the info. Hmmm. I see. I honestly do not know if this car does or not. It is my GF's car. I'm guessing it does have because if I remember right after coming home at night with her sometimes when I worked days way way way back, the lights stayed on for a certain amount of time after. I should look in the manual to be sure though. I did just check the connections at the bulb sockets and each one has power going to it. Her car does not have fog lights though and there is no fuse or relay in those slots on the fuse panels. I hate electrical on cars. I'm not good at it and my knowledge on it is literally nearly none. I wouldn't even know where to run the damn ground wire to check. My one friend knows a good amount and he gets off at 2:00 today. Maybe he can help past what I have checked so far.
Well, with everything I've done so far it seems to point to the Multi switch as the possible culprit. Got one from advance and going to attempt to install it tomorrow.
Had Same thing happen to my friends car same car problem was the all in one dimmer switch that runs the directional and high/low beam replaced it and working fine since
I got it figured out. It was the Multi switch/turn signal. I would have never guessed it was linked to the headlights. Figured I'd post this as solved. Thanks for the other reply too.
Its linked to the headlights thru the high beam side of the switch in the multi function switch. They often fail on the signal side of the switch, and the hazards lights.