My low beam headlights do not work as daytime running lights or manually with the headlight knob pulled out . The high beam headlights however do work if I have the knob pulled out all the way with the dipper switch engaged . This is a 2004 Regal GS . Is there a circuit breaker I need to reset somewhere .

Sampson, sounds like a bunt out bulb, which will need changed.
If you feel comfortable doing it yourself. Basically three screws, and you have to pull one plastic fastener from the fascia (bumper) and pull the bumper back a bit, and pull the assembly out. I believe it is in the manual, not bad to do. I will post a link to tell or show you how to do it. Press the helpful button

Headlight Change 2005 2009 Buick LaCrosse 2006 Buick LaCrosse CX 3 8L V6

2008 Buick LaCrosse Headlight Replacement

Thread how do replace the headlight bulb in 2005 buick lacrosse

Headlight Bulbs

Headlamps Inoperative - Low Beams

Step

Action

Value(s)

Yes

No

DEFINITION: This diagnostic procedure should only be used if the high beam headlamps are operating properly and the low beams are inoperative.

1

Did you perform the Headlights System Check?
--
Go to Step 2
Go to Headlight System Check

2

1. Turn the headlamp and panel dimmer switch to the ON position.
2. Move the headlamp dimmer switch to the LOW position.
3. Backprobe the headlamp dimmer switch connector with a J 35616-200 from cavity A to ground.

Does the test lamp light?
--
Go to Step 3
Go to Step 5

3

1. Remove the daytime running lamp relay.
2. Connect a J 35616-200 at cavity G5 to ground.

Does the test lamp light?
--
Go to Step 4
Go to Step 6

4

1. Re-install the daytime running lamp relay.
2. Backprobe cavity B at the high/low beam headlamp with the headlamp dimmer switch in the LOW position.

Does the test lamp light?
--
Go to Step 7
Go to Step 8

5

Replace the headlamp dimmer switch.

Is the repair complete?
--
Go to Headlight System Check
--

6

Repair the open in CKT 359 (PPL) between the headlamp dimmer switch and the daytime running lamp relay.

Is the repair complete?
--
Go to Headlight System Check
--

7

Replace the high/low beam headlamps.

Is the repair complete?
--
Go to Headlight System Check
--

8

1. Inspect for an open in CKT 12 (TAN) between the daytime running lamp relay and S120, repair as necessary.
2. Replace the daytime running lamp relay if no open was found in CKT 12 (TAN) between the daytime running lamp relay and S120.

Is the repair complete?
--
Go to Headlight System Check
--

[Information] For a 2002 Toyota Camry, the Daytime Running Lights (DRL) operate utilizing the High Beams (inner Lamps closer to the center of the vehicle front) at a reduced power.

[The troubleshooting process:] Review the Owner's Manual and ensure the test configuration matches the following criteria:
1. According to the 2002 Toyota Camry Owner's Manual (Check your Owners Manual):
"The DRL system will make your headlights come on at a reduced brightness when:
The light switch s in the "DRL" position.
The ignition is on with the engine running.
The headlight switch is off.
The parking brake is released."

2. Set the Test Conditions according to Step 1 above.

3. Check the headlight bulbs to ensure they are not burned out. If one burns out, there is a fair chance that the other would have burned out at the same time. Replace as necessary. In this case, if the high beams operate, the DRLs should also operate.
4. Test the system, ensuring the step 1 conditions are set. (Engine running, Multi-function Switch on Turn Signals in "DRL" position, headlight switch off (repeating what the manual says -- it should be obvious that in the "DRL" position, the headlight switch should be off / do not have the switch positioned to "High Beam"), and the Parking Brake "off").
5. If DRL lights do not work, check the engine compartment Fuse and Relay Box. there is a 5 Amp DRL fuse -- replace it with the spare. Test (step 4).
6. If it does not work, swap around or replace relays -- there are three (3). Any one of them could be bad (stuck or burned out). Test (step 4).
7. Other less likely possible issues could be that the Multi-function Switch is broken or a connection / wire is broken. [Beyond the scope of this process.]

My problem was that the test configuration did not have the engine running and parking brake off - Step 1. Problem solved with much thought, repetitive tests on the vehicle and going back to the basics -- what does the Owner's Manual say and where are the applicable fuses and relays located?

First, be sure that the headlights are actually coming on. These cars have daytime running lights that use the headlight bulbs at a lower voltage. If the car is only using the daytime running lights, the tail lights will not be on with the headlights. The multifunction lever always turns on the high beams when you pull on it (it's called 'flash to pass'). Make sure the headlight switch is working, and also check the headlight circuit breaker.

The blinking light is telling you that you have a headlight out, if you look the service light should be coming on when the light stops blinking.
Replace the head light and all should be fine.

As you described the problem the solution is to replace the headlight bulbs, they have two elements one for normal lighting or low beam and one for high beams. the elements for the low beams are continuously used and are subject to burn sooner.

Sounds like you need a bulb,the daytime running lights send power to the high beam wire so they look like low beam lights are on but really they are high beam lights running on low voltage.

Pull the head light switch and check it for out put.Do you have high beams?Check the low beam headlight bulbs.If you have high beams,and low beam bulbs are good,replace the dimmer switch.

Well...lets start with the obvious. Check fuses and NEVER piggyback any stereo or security stuff into their fuses...you dont want the lights to shut down during a night drive!!
Check under the hood for a relay center...also has some fuses there as well.

The Daytime Running Lamps are a "straight through wiring configuration". Doubt it even goes through a headlight switch at all.
But the regular lights do.
Unless you've worked on the front of the car and forgot to plug the headlights back in, do this...
Turn the light switch on...looking at the instrument cluster , can you make the high-beam-indicator light come on?
As you rotate the headlight switch knob...does the instrument panel lights brighten or dim? You probably have a faulty headlight switch...auto stores have them...they simply plug in.

ya know it kinda sounds like the headlight switch that switches from high beam to low beam has a bad contact. You don't have one of those 4-beam modules that turn on all 4 lights on high beam do you? that thing screwed my whole headlight system up, I ended up throwing it in the trash.

I have the chiltons and haynes manual, I'm sure between the two we'll find a good diagram. I gotta get my youngin to open house at school, but I'll pull the books out and send you the wiring diagram.