5 Defects in modern car headlights you should know and repair

5 Defects in modern car headlights you should know and repair

There is this saying that usually follows a modern car…”I bought the new model, so nothing can go wrong with the parts.” Well, when it comes to car headlights, I would like you to know that the fact that it is modern does not necessarily mean that the headlight of the car cannot get faulty. Unfortunately, most drivers do not place a priority on headlight problems, when in fact, it’s crucial to pay attention to them. Before you attempt to buy your next new car, here are 5 defects in modern car headlights you should know and repair.  

Five common car headlight defects

1. When headlights look dull:

Headlights are predominantly made of plastic and overtime, the sun’s rays beating down on this plastic may cause it to have a disgusting yellowish color. The process is known as oxidation and it may be a serious issue as it dulls the headlights and gives it an impaired lighting when driving at night. 

However, the sun is not the only thing that can affect car headlights, other factors like the rain, wind and even snow may discolor the headlight. 

What to do? 

how to make dull headlights clear again

Usually, a good clean up would do wonders to your headlights and make it as good as new. 

There are several methods to clean your headlights, and the better news is that you can do it with everyday items you have in the house and do it yourself. 

An example of a good headlight cleaning agent is toothpaste. When the headlights are polished with toothpastes, it can take care of the oxidation. 

Other cleaning agents include

  • Sand paper
  • Soap and water
  • Restoration kits

However, the best method to clean your headlight when they are oxidized is to use a good and recommended headlights restoration kit

2. When one headlight stops working

First of all, there is nothing wrong with your car when this happens. It is perfectly normal for one of the headlights on your car to suddenly stop working. When this happens, it is usually because the bulb inside is burnt. And don’t freak out about why the second headlight isn’t burnt even when you bought them at the same time. Their lifespans may differ, but if one bulb goes out, the other isn’t far behind. 

What to do? 

When one headlight stops working

The only thing to do in this regard is to change your headlight bulb. Now, as earlier mentioned, when one bulb goes out, the other isn’t so far behind, so it is usually best to change both bulbs and you would find that your headlights are back to normal. 

Also, after replacing them, try to test them to see if they work perfectly, and ensure the viewpoint of the headlight is adjusted properly because you may have tampered with it when you were replacing. 

3. When headlights keep going on and off randomly

Sometimes, it may seem like your headlights have a life of its own as they would flicker on and off at intervals on their own. Needless to say, this is very dangerous and it is best to leave the car in the garage while it is being diagnosed. It is best not to take your car out at night if it has this issue. 

What to do? 

When headlights keep going on and off randomly

Headlight flickering could mean warning signs that your bulb is about to die, or maybe the wiring is problematic. Sometimes, it could even be something as random as your stereo drawing power from your headlights, hence the flickering. However, the best thing to do is to take the car to a mechanic or invite an expert over to come take a look at it to be sure what the exact problem may be. 

4. When both headlights stop working

This is a very rare headlight defect, but when it happens, unlike when one headlight stops working, it is very unlikely that the bulbs are faulty. In this regard, the problem may be a little more complicated. 

What to do? 

When both headlights stop working what to do

The problems may be emanating from the headlight fuses, relays or switches, so you would need to test them out to be sure which it is. If it is a blown fuse that is relatively easier to fix than when it is the relays or switches. Should you be faced with a bad headlight relay, try these 5 simple fixes. If you find it challenging, you are advised to take the car to a mechanic for proper diagnostics and fixing.  

5. When the beams are weak

This is another common headlight defect. Sometimes, the headlights may be working perfectly but the beams may be weak. The problem is usually that the headlight bulbs are ageing and need replacement. Foggy headlights can also weaken beams as well. 

What to do? 

When the beams are weak

You could clean the headlight covers thoroughly and apply UV sealant. If the problems still persist, then you may need to replace the bulbs altogether. 


One major dilemma you may be facing right now is if you should attempt to fix these issues yourself or hand them over to a mechanic. Well, there is no straight answer to that as the problems listed here differ in complications, while replacing your headlights is easy, issues involving wiring, relays and switches may be a bit more complicated. 

Therefore, to create a perfect balance, it is okay to attempt the easier hacks like cleaning your foggy headlights, and replacing the bulbs, but when the problems are more complicated, it is best to hand it over to an expert. 

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