Bright went out after replacing the headlight

Make sure you will have enough ventilation. Most of leds have fan built in

Yes the light will handle the small amount extra current required by the Halogen bulbs. It is best of course to inspect the switch to see that it is on good shape, depending on the year of the car and the switch design used some do fail when the car is used for long periods of time with the lights on in slow speed traffic. If the switch has suffered overheating the contacts will be disclosed on the switch and the wire connector to it. If the contacts are in good condition they will be a bright brass color.

Halogen lights will draw more voltage than the standard lights and will more than likely cause electrical problems by wires and switches and such getting overheated.
Larger tires will make your speedometer read that you are going slower than you are actually going.

I think that many 1990s and even some 1980s GM vehicles with seemingly 4 headlight systems actually use only 2 at a time.

My 1990 Oldsmobile Cutlass Calais, for instance, had 2 high beams that went on independently of the 2 low beam lights when switched with the turn signal lever.

In the 1970s the GM vehicles had 4 headlight systems where all 4 headlights would go on, but they used sealed beams rather than the capsule lights that are used nowadays.

For instance, our 1976 Cadillac Seville has a 4 headlight system that lights up 4 headlights on the high beam mode.

Good luck on seeing at night with the current set up.

Have you tried to change the headlights?

REMOVAL & INSTALLATION Sealed Beam NOTE: If vehicle is equipped with headlamp doors turn the headlight switch ON. Open the hood and locate the power distribution center. This center is located in the front of the left front strut tower. Remove the cover from the center and remove the Headlamp Close Relay. This will prevent the headlamp doors from closing to provide easier servicing. Turn the headlight switch to OFF, then perform this repair.

1. Remove the headlight bezel.
2. Unhook the spring from the headlight retaining ring if so equipped.
3. Unscrew the retaining ring and remove it. NOTE: Do not disturb the two long aiming screws. Conventional and Halogen headlamp sealed beams units are interchangeable in pairs, but it is recommended that they not be mixed together (one halogen and one conventional). It is fine to upgrade from conventional bulbs to halogen, but do not change from halogen bulbs to conventional bulbs, especially if the vehicle came equipped with halogen bulbs.
   
4. Unplug the old sealed beam from the engine electrical wiring harness.
5. Extract the old bulb from its mounting bracket. To install:
   
6. Connect the replacement bulb and install it into the receptacle (check operation of headlight before completing repair).
7. Install the retaining ring and secure it in place with the retaining screws. Connect the spring.
8. Install the headlight bezel.

Aero Headlamp Aero headlamp systems use replaceable halogen bulbs that are mounted in aerodynamic, molded plastic lens reflector assemblies. NOTE: Lens fogging is a normal condition and does not require service, as moisture will vent from tubes behind the lens on Aero headlamp-type system. EXCEPT PREMIER AND MONACO It may be necessary to remove the entire headlamp assembly if enough access cannot be gained otherwise.

1. Locate and remove the wire connector behind the headlamp assembly in the engine compartment. It may be necessary to remove certain items in the engine compartment to gain access to the bulb wires.
2. Rotate the bulb retaining ring counterclockwise 1?4 turn and remove the ring, bulb and bulb holder from the lens assembly. The bulb holder has alignment notches. NOTE: Do not touch the bulb with bare fingers or any possibly oily surface, since reduced bulb life may result! Fig. 1: To remove the light bulb, first unplug the headlight electrical connector, then . . .
   Fig. 2: . . . remove the light bulb socket retaining ring
   Fig. 3: Rotate the light bulb socket 1?4 turn counter-clockwise, then pull it straight out of the lens assembly
   To install:
   
3. Wearing gloves or holding the replacement bulb with a cloth rag to keep oil off of the bulb surface, insert the bulb into the rear hole of the headlamp assembly. Make certain that the alignment grooves and tabs line up, push the light bulb into the assembly until seated flush, then turn the bulb clockwise 1?4 turn.
4. Plug the electrical light bulb wiring harness into the new light bulb. Install any items removed from the engine compartment.

PREMIER AND MONACO Unlike the other vehicles covered by this manual, the removal and installation of the headlamp bulbs in the Premier and Monaco models requires the extraction of the entire headlamp lens assembly.

1. Remove the grille-to-headlamp assembly attaching screws.
2. Disconnect the headlamp aiming cable from the aiming screw end.
3. Remove the headlamp assembly attaching bolts from above and behind the lamp assembly and separate the lamp assembly from the vehicle.
4. Unplug the headlamp wire connector. NOTE: Do not touch the bulb with bare fingers or any possibly oily surface, since reduced bulb life may result!
   
5. Rotate the socket counterclockwise 1?4 turn and pull the socket from the back of the lens assembly. Fig. 4: Remove the bezel retaining screws to loosen the headlamp assembly - Premier and Monaco
   Fig. 5: Detach the headlamp wire connector - Premier and Monaco
   Fig. 6: Once the headlamp assembly has been removed from the vehicle, the various light bulbs can easily be removed - Premier and Monaco
   To install:
   
6. Wearing gloves or holding the replacement bulb with a cloth rag to keep oil off of the bulb surface, insert the bulb into the rear hole of the headlamp assembly. Make certain that the alignment grooves and tabs line up, push the light bulb into the assembly until seated flush, then turn the bulb clockwise 1?4 turn.
7. Plug the headlamp wire connector back into the headlamp bulb.
8. Install the assembly into the vehicle and secure in place with the mounting bolts.
9. Connect the headlamp aiming cable to the aiming screw end.
10. Install the grille-to-headlamp assembly attaching screws.

Most vehicles are equipped with Halogen bulbs that are small bulbs that are replaced from under the hood behind the headlight bezel assembly.
They have a twist turn method generally to remove/replace hiowever they cannot have your hand come in contact with the glass bulb as the oils on your skin will in fact reduce the halogen bulbs life as it gets extremely hot burning the oil off the lense shortening the bulbs existence.
Remember to replace the bulb with the proper bulb as you may find two or three different applications of halogen bulbs for the same vehicle, they all have a purpose, they go from bright to brighter to brighter each increase in candle power also increases in price of the bulb, a typical standard priced Halogen is approximately $9.95 and up.

Any mechanic can aim your headlights for you , but I would consider buying new bulbs. Even if your car has halogens , they do become less bright over time.
Some of the new bulbs on the market will light up 2 to 3 times as far as older halogens.

if equipped with sealed beam lights,remove screws from trim panel surrounding headlights.remove 4 screws from headlight bezel [silver rectangle that retains bulb] unplug connector.do not remove adjustment screws. halogen bulbs may be reached from engine compartment,behind light assembly.

You do not need to take the headlight assembly out. It is not a sealed beam. There is a ring that locks the light bulb in, found on the back. The drivers side is much easier if you remove the battery. As with all Halogen bulbs, do not touch the bulb with your fingers as it will shorten their life.

So, when u turn on the high-beams, the indicator light goes on, but u still have low beam headlights only? Check the headlight (either one), and see if by chance both high beams burned out at approx. the same time. U don't specify what year, I'm not sure if u have a replacement bulb, or a sealed beam headlight to replace. If the high beams are both ok, then it must be the headlight high beam switch. Let me know what u find.