My headlights are not working correctly

my low beams won't come on when i start the car instead the high beams do. all the switches seam to work fine and all other lights come on and work just fine. every now and than the low beam come on and the light on the dash comes on and i turn the high beams off and everything seam to be okay but than like a minute later the low's just turn off and the high beams come on automatically. i change the headlight and the bulbs and it didn't help. oh and i can't switch the high beams off when they are on. the light switch will just turn on all the other lights only.

My car has

Experienced mechanics share their insights in answering this question :
Hi there. Most of the time this is caused by a bad headlamp switch. When the switch fails, it will cause this to occur. If the switch is fine, then it may have an issue with the headlamp relay. I typically take my voltage meter and test the circuit starting at the headlamps until I find where the voltage is being lost.

If you want to have your headlamps fixed, consider having a certified mechanic, such as one from YourMechanic, come to your home or office to inspect the headlights and suggest any necessary repairs.

How to Identify and Fix Common car Problems ?

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A bad headlight relay is among the more common reasons we see for low beam headlights not working while the high beams do. You see, the low and high beams each have their own relay, which is essentially an electrical switch. Like fuses, sometimes relays go bad.
The likely cause is a fuse, headlight relay, headlight switch, dimmer switch or a wiring fault. About the only cause that is an easy fix is a blown fuse. Consult your owner`s manual to locate the main fuse for the headlight circuit and replace that fuse with one having the same amp rating.
You`ll need to replace the bulb, switch, or relay. If just one bulb fails to work in either high beam mode or low beam mode, it may be the bulb. Most headlight failures that are limited to just high or low beams are related to a relay or the high beam control switch.
Headlight Fuse or Relay

If a headlight fuse blows, it could cause the headlights to stop working. Most headlight systems are also designed with a relay that switches the power between low beam and high beam headlights. If this relay goes bad, it could allow power to the high beams, but not the low beams.

Used in “flip-up” lights, which fold out of the body of the vehicle, headlight closure relays are essential for headlight operation. This relay is located in your main fuse box or panel.
There is a good chance that your ballast is the cause of your lighting problems if your headlights are dim, changing colors, buzzing, or flicker. When inspecting it for potential issues, any burn marks, leaking oils, or swollen casing are indicators of failure.
Connect the test light to battery power. Touch the test light probe to the socket`s ground on the connector terminal. If the test light glows, check the bulb socket and connector for corrosion or a bad contact. If the test light doesn`t glow, check the ground side of the circuit for an open.
Where is the Headlight relay located? You can find the Headlight relay in the electrical distribution unit of the engine block. In case you need support locating the relay, refer to your owner`s manual.
As you stand in the front of the car, have the assistant turn the headlights off. Next, put the dark cloth or cardboard over one headlight, and have the assistant turn the headlights on. Find the adjusting screw and turn the screws slowly clockwise to raise the height of the lights or counterclockwise to lower them.
The blown fuse will be apparent because the wire element within will have melted or burned from the higher electrical current. You can also use a test light or a multimeter to identify the dead fuse without having to pull it out. Both tools are affordable and easy to use.
Parts cost on average $58.92 – $72.01, and services cost $116.82 – $142.78. This repair takes on average 0.99h – 1.21h for a mechanic to complete. If your headlights don`t turn on or you can`t turn your high beams on or off, you may need a headlight switch replacement.
Most of the time both bulbs are bad. The connections to the bulbs could be faulty as well. If you`re unable to pinpoint the issue, have a certified technician, like one from YourMechanic, diagnose your lights firsthand for an accurate repair.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

All dashboard lights and tail lights do not work after driving through a lot of snow. Headlights work. And brake lights work.
ANSWER : Hello. We’ll be happy to help you. There are a few things that I recommend checking to discover why your lighting system is malfunctioning. The headlight dimmer switch should be checked. Along with the wiring harness above the right front tire behind the fender well cover. Also
the main fuse under the hood should be inspected because other people with your particular vehicle have had similar lighting issues if that fuse goes bad. It will be a great idea to check the rest of the fuses in that area too while checking the main fuse. Once the fuses are checked inside of the main fuse box then I would check the fuses inside of their interior fuse box. The interior fuse box should be located on the driver side of the dashboard near where your legs would be. If you need more assistance with repairing your vehicle please keep in mind that our organization provides Mobile Mechanics who can help you diagnose and repair your vehicle, all at competitive rates.

One of my car’s headlights does not work
ANSWER : Hello. There are 2 devices in the front wiring of your vehicle called "Signal Acquisition Modules." One is for the left side of the front, the other is for the right. They act as an electrical "router" and power distribution module for electrical loads up front. These modules take signal pulses from light switches and other controllers, and turn on power to the requested device.

The SAM units have fuses in them, just as a traditional box would. I would check the fuses in each SAM for both low and high beams, then check the igniters for the xenon low beams. If this seems a bit intimidating, I recommend having a certified mechanic, such as one from YourMechanic, come to your location to inspect for any electrical problems and suggest the needed repairs.

My dash board don’t work my front light work when I change my light into high beam and my back window won’t go down
ANSWER : As unfortunate as it is, your vehicle would be considered flood damaged. Diagnosing electrical problems in a flood damaged vehicle is nearly impossible. This would take many hours or even days to determine which wiring harnesses and circuits have been affected. Then nearly all of the wiring under the dash would likely require replacement as well as many sensors and switches. On a BMW vehicle, the amount of wires and switches are likely more than that of a lower end vehicle. Due to the inefficiency in cost, you would likely be able to purchase another BMW like yours for less than what it would cost to fix your car. Many insurance companies would consider this type of damage to total out the vehicle unfortuantely.

Windshield wipers stopped working. They’ll suddenly stop working then suddenly start working again. Has been happening for a week.
ANSWER : The problem you are describing likely stems from an intermittent electrical fault in the wiper circuit. The windshield wiper system uses a small electric motor to move the wiper arms that you see on the windshield. That electric motor is controlled through a switch, relay, fuse, and wiring. One, or more, of those electrical components has failed although it is also possible that the mechanical arms are binding (seized, if the lubricant has dried out) thus causing the electric circuit to the motor to overload. Regardless of the underlying fault, if you request a non functioning wiper diagnostic/repair, the responding certified mechanic will get this taken care of for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

Both R&L low beam headlights quit working simultaneously.
ANSWER : Hi there. Check the switch to the headlights and see if there is a break in the wiring. Check the fuses and see if there is any fuse that are blown. If the fuses are good and there is no break in the wiring, then either the switch has failed or the ballast resister has failed on the low beam circuit. Turn on the switch and check for power coming out of the switch. If there is power to the switch and power out of the switch, then I recommend replacing the ballast resister. If there is no power coming out of the switch, then the switch needs replaced. If you need further assistance with diagnosing the low beams, then seek out a professional, such as one from Your Mechanic, to help you.

My headlights are not working correctly – 1996 Chevrolet Blazer
ANSWER : Hi there. Most of the time this is caused by a bad headlamp switch. When the switch fails, it will cause this to occur. If the switch is fine, then it may have an issue with the headlamp relay. I typically take my voltage meter and test the circuit starting at the headlamps until I find where the voltage is being lost.

If you want to have your headlamps fixed, consider having a certified mechanic, such as one from YourMechanic, come to your home or office to inspect the headlights and suggest any necessary repairs.

My AC does not always work. If I fiddle with the blower knob I can ususally get it to work on the lowest setting.
ANSWER : Hi There,
It sounds like you may have a faulty blower motor resistor. The highest speed setting may still work because in most cars in the highest fan speed settings the current bypasses the blower motor resistor. In some cars, if the resistor is failed, the fan may stop working completely. Another reason a blower motor resistor may fail is when the blower motor has a mechanical problem or when a foreign object jams the blower motor fan blade and prevents it from spinning freely. This leads to increased current through the resistor and causes it to overheat and fail. I would suggest having an expert from YourMechanic come to your location to diagnose your system to determine what may be causing the fan not to work properly.

Lights don’t work correctly
ANSWER : The first thing to check is the connector where it was replaced. A mechanic would need to check to see if the connector is wired correctly and that it has the proper power and ground to power the headlight. You may just have a loose wire or a bad bulb. Also the wiring may have been damaged from the water exposure. I recommend having a technician come and diagnose your light issue and perform any necessary repairs to have this fixed.