Signs Of A Bad Headlight Switch & How To Replace?

Your headlights aren’t working. And you’re wondering how they could end up unresponsive when you can’t see any damage at all. In some cases, the headlight switch is to blame.

In this article we will discuss about the signs of a bad headlight switch and how to replace them.

Getting To Know Your Headlight Switch

Also called the dimmer switch, the headlight switch is a piece of electronic device in charge of controlling the car’s headlight functions. The switch is responsible of accessing and controlling your lights – be it daytime running lights, high beams, or headlamps.

In most vehicles, the switch can be found sharing a portion of a switch lever commonly attached on the steering column. Further, it can also be found as knobs or buttons mounted somewhere in your interior.

Due to consistent, regular use, switches can also unsurprisingly wear out just like any other piece of electrical device. Eventually, you may have to replace them. That is why it’s essential to be vigilant of the symptoms of a bad or failing headlight switch.

Signs of a Bad Headlight Switch

The following is a list of symptoms that notifies you of possible failing switch issues.

High Beam Issues

A good sign that your switch may already need replacement is operational issues on high beams. If you ever experience having a hard time activating the high beam, then that’s it.

Headlight switches utilize a type of lever which it pulls backwards and locks it into place to turn the high beam on. After some time, the switch can break, making it unable to activate the high beam headlights.

Note that a broken switch can still be able to trigger the high beam. However, it has the tendency to pop loose causing the high beams to disengage.

Difficult To Switch Between Modes

Another common sign of a broken switch is having problems in switching between modes. A faulty switch can only activate a specific mode, or may result in erratic and alternating modes.

Noticing your lights to come on and off intermittently means there is a problem with your switch. It even imposes a serious, safety hazard due to obstructions in your visibility while driving.

Your Lights Don’t Work

If your lights are brand new or if you’re sure they don’t have any issues of some sort, but they simply won’t come to life; it’s an obvious sign of a bad switch.

If you’ve tried turning on the switch but none of the modes can activate the lights, it’s a clear indication of a switch failure. This situation comes as a great burden especially during night. A car with no lights during night is a perfect equation for unsafe driving.

This is where replacement comes into the picture. When you experience any of the symptom above, take immediate actions in replacing your headlight switch.

Important Note: Go first to your dealership and purchase a headlight switch for your specific car model.

Safety First

Before doing any car work, you should wear first safety equipment such as gloves and safety goggles. Since you will be doing things on your own, it would be wiser to play safe as to prevent possible injuries should you do otherwise.

How To Replace Headlight Switch

You can always call a certified mechanic to handle things for you. However, it won’t cost you much to try things on your own.

Labor costs in the US today can be as much as $70 (or more) while headlight replacement parts cost more than a hundred dollars, depending on the make and model.

Spare yourself the cost of labor; save it or spend on something else by trying to replace your headlight switch on your own.

The following is a set of reliable instructions you can follow to properly replace your headlight switch with a new and functional one.

Disconnect the Battery First

  1. It’s always wise to keep in mind that whenever you do any car operation, always turn OFF your vehicle.
  2. Open your hood and find the battery. Your battery can be found near the engine’s front part or at the side.
  3. Your battery should have a black cable attached to it; it’s the negative (-). Find it. There must also be a red cable indicating positive (+). Your target is the black one. And do NOT touch the red one.
  4. Disconnect the negative cable from your battery. A spring clamp attaches the cable to the battery. This spring clamp can be easily squeezed and released.
  5. If squeezing the clamp together won’t remove the cable, try wiggling the cable back and forth while you squeeze until the spring clamp is removed.
  6. After removing the clamp from the battery, prevent the cable from touching the battery.
  7. Hang the cable out of the way of the battery. A single contact between the negative cable and the battery can reactivate the car’s electrical system, putting all the precautionary measures you’ve done in vain.

Headlight Switch Replacement

  1. After disconnecting the negative cable from your battery, wait for about 10 minutes before proceeding to the next step. This technique can discharge the capacitors of the airbags.
  2. Start prying the retaining ring holding the switch in place.
  3. Do not forget to remove screws around the switch.
  4. Now slide the headlight switch away from the dash with utmost caution.
  5. Proceed by removing the wireplugs.
  6. Attach a spring clamp to the plugs to prevent them from falling into the lower interior. You don’t want to go swimming on the floor looking for parts.
  7. Put the light switch in an “on” position.
  8. Start pressing the headlight case button then remove the switch.
  9. If dealing with more than one release button, you can use a screwdriver.
  10. There are also cases where you have to remove the decorative bezel. Do this by removing the nut at the bottom part of the switch.
  11. Now attach the new vehicle headlight switch properly into the respective housing.
  12. If necessary, replace the shaft nut and bezel
  13. Start reattaching wire plugs in a careful manner. Avoid bending any contact.
  14. Gently and without bending connecting wires, slide the switch and the housing back into the dash.
  15. Secure mounting screws back to where they are initially fixed.

Reconnect the negative battery wire

  1. Squeeze the clamp to the location from which you previously removed it
  2. Now it’s time to test your new headlight switch.
  3. Try switching into different modes.

Your headlights should now work properly. If it doesn’t work the first time, you can troubleshoot the problem by dissecting each step you took and assessing whether you overlooked something.

Since you are working alone, it is also advisable to test during night or in a dark garage so you won’t have a hard time testing the lights if they’re already working fine or not.


Part of being a responsible car owner is trying to handle automotive issues on your own. Of course, calling for a mechanic is not a bad idea at all.

But it is more fun and exciting to take things into your hands. Not to mention the great sense of fulfillment after overcoming a problem.

Learning the signs of a bad headlight switch and how to replace them is an important do-it-yourself skill which comes quite handy when you need it.