I Put New Headlights Bulbs In My Truck And I Can Turn Them On And They Both Me.

1. Faulty bulb: It is possible that the new bulb you installed is faulty or damaged and is not designed to handle high beam use. You may want to try replacing the bulb with a new one to see if that fixes the issue.

2. Loose Wiring or Bad Connection: Inspect the wiring and connection to the headlight bulb. If the wiring or connector is damaged, severed, or loose, it can cause inconsistent power and result in dimming. Re-wiring or replacing the connector may be necessary.

3. Bad Relay or Switch: A faulty high beam relay or switch can cause one light to dim while the others stay bright. A mechanic can test it and relatively easily replace a faulty high beam relay or switch.

4. Alternator Failure: The dropout voltage can cause the dimming issue in your headlight. In this case, the alternator must be repaired as quickly as feasible.

1. Check the connections: Make sure the wiring and connections on both headlights are secure and tight. Loose connections can cause issues with the electrical current flowing to the bulb.
2. Check the bulb: Double-check that you installed the correct type of bulb on the driver's side headlight. If the bulb is the wrong type or not properly seated, it can cause issues with the high beams.
3. Check the wiring: Inspect the wiring for any signs of damage or wear. Broken or frayed wires can cause electrical issues that affect the performance of the headlights.
4. Check the headlight housing: Make sure that the headlight housing is properly aligned. Misaligned or loose housing can cause the light to shine in the wrong direction, which can lead to dimming or other issues.

1. Check the connections: Make sure that the headlight bulbs are properly seated in the headlight housing and that the wiring harness is securely connected. Loose or damaged connections can prevent the headlights from functioning.
2. Check the fuses: The headlight circuit in your truck is protected by fuses. Check the owner's manual or the fuse box under the hood to see if any of the headlight fuses are blown. Replace any blown fuses with the correct amperage rating.
3. Check the headlight switch: The headlight switch controls the power to the headlights. If the switch is faulty or has a loose connection, the headlights may not turn on. Try turning the switch on and off a few times to see if the headlights respond.
4. Check the ground connections: The headlights require a good ground connection to operate. Make sure that the ground wire from the headlight housing to the body of the truck is securely connected and not corroded.

If none of these steps resolve the issue, you may need to take your truck to a professional mechanic or auto electrician to diagnose and repair the problem.