How Do I Stop My Lights from Flickering When Bass Hits?

How to Stop Car Lights from Flickering When Bass Hits

IF you have a stereo in your car, and it has decent bass, you’ve probably noticed the phenomena of flickering lights when the bass hits. Unless the lights are specially designed to go on and off to the beat, this is not something that’s supposed to happen. We understand how annoying it can get at times.

Here in this article, you’ll find out the possible reasons behind this happening, whether it affects your car in any way, how does it affect your car, and how to prevent it from happening. So, turn up the music, and fasten your seatbelt. Let’s take you for a ride.


Why Do the Lights Flicker, Anyway?

Reasons Why Car Lights Flicker

The answer is quite simple. The lights go on and off due to a shortage of power. When your subwoofer is big, that… along with a powerful amplifier draws a huge amount of current. It varies depending on what kind of music you’re listening to and in what type of volume.

If you’re listening to music that has a hell of a lot of bass, say heavy metal or rock, then your amp is going to drain a lot of power. On the other hand, if you’re listening to something soft and mellow like indie or folk with mostly acoustic instrumentations, then your amp is not going to have much appetite.

In more technical terms, when the electrical system in your car, along with the alternator, can’t provide the power that is required by the subwoofer’s amplifier, then the voltage in your car comes to a sudden drop. This is what causes the lights of your car to dim out every time the bass hits hard.


How Do I Tell If My Car’s Voltage Is Dropping?

how to check car voltage dropping

The lights flickering itself is a sign of a voltage drop or power shortage. Apart from that, other indicators imply you’re having a scarcity of power in your car.

If you want to get a bit more technical, then there’s a way through which you can actually test if the voltage in your car is at the right level. To perform this voltage-drop test, you simply need to get a gear called a ‘Multimeter’. This device measures the voltage drop across a load device called a ‘Conductor’.

To measure your voltage drop using a multimeter, at first, you’d need to configure it. You can do it in 3 simple steps. Here they are:

  1. Take the black probe of the multimeter and put it inside the socket that’s labeled ‘COM’ for ‘common’. This is the socket that’s used for all measurements. Once you get it in, you won’t need to remove it or change it if you need to measure other units of power, say watt or ohms.
  2. Next, you’ll find a socket that has a ‘V’ on it. Put the red probe in there. It’s also the socket that has an omega (Ω) indicating resistance.
  3. Now, turn the big rotary dial on the settings panel, the one with a large ‘V’ on it, for DC voltage. Don’t confuse it with the one for the AC voltage. The DC one has a V with solid lines over it, ad the AC one has wavy lines for distinguishing. In case you don’t have an auto-ranging meter, you can select the voltage range to measure a smaller amount of voltage such as 2V.


Is It Bad for My Car If the Lights Flicker?

Well, to be frank, nothing will happen to your car if the lights go on and off when the bass hits. That being said, the concern of something happening to you still remains. Especially when you’re driving at night, this may be an issue for other drivers on the road.

Not just other drivers, even you won’t be able to see the road in front of you within dimming headlights. That could lead to various kinds of accidents that can lead to damaging your car, and well, you.

Not to mention the factor that if your headlights keep dimming some motorists may think you’re ‘flashing’ them with your headlights.

In a nutshell, no. Flickering headlights do not have any direct impact on your car’s overall performance but it has a high chance of increasing your probability of getting an accident. Better get them fixed before this happens.


How Do I Stop the Lights from Flickering?

The first and foremost thing to do is to get your car’s electrical system checked by a qualified technician. There are some auto parts supply stores that do the checking part for free.

If you see that your electrical system isn’t strong enough to power your amp along with the subwoofer, then you should get that fixed at first. You could consider getting a larger alternator, in some cases.

The basic idea is to get your system to produce enough power for your amp and subwoofers to feed on. Music that has a lot of bass requires a lot of power to be played. If your electrical system is incapable of providing that power, that’s when the lights flicker.

Here are some suggestions that might help you to prevent the lights from flickering:

Keeping The Volume Down

How to Stop Car Lights from Flickering - Keep Volume Down

I know, it doesn’t sound like much of a big brain moment but lowering the volume just when the bass hits, really works wonders when there is a shortage of power.

Although this idea may not be preferred by you if you like your music loud. Once the volume is lowered down, your amp won’t try to draw in more power than the electrical system is capable of providing, and there will be enough power left for the lights to keep shining with consistency.


Downgrading The Amp

How to Stop Car Lights from Flickering - Install Power Amp

The next thing you can do that involves your sound system is downgrading your amp. Basically, this is also suggesting that you should compromise with the sound quality if you want to stop your headlights from flickering. But bear with me, this actually works.

If you install a power amp that drains less power, you’ll be able to avoid the embarrassing situation of having to power a beast of an amp with an ordinary charging system. Saving the headlights from going all disco in the process.


Upgrading The Alternator

How to Stop Car Lights from Flickering - Upgrade Car Alternator

This is the solution that I’ve already mentioned before because it seemed like the best one among all the others that I’ve stumbled upon while dealing with the problem myself.

Let me elaborate a bit further. If you install a high-performance alternator, you’ll be able to get even more out of your charging system, resulting in zero to no flickering of the lights.


But What If Sound System Isn’t the Problem?

Many things can cause your headlight to flicker. Apart from power shortage, it could also be a failing alternator or simply bad wiring.

While you can hire a professional to check every nook and cranny of our car to see if the charging system is alright, there are also a handful of DYI ideas that you can try out:

Check The Headlight Wires

Ways to Fix Headlight Flickering - Check Headlight Wires

If the connections your headlights have are loose, or they have very old wires, then that could be possible causing behind it. There’s this thing called a ‘Fuse’.

What it does is, blows up or melts and blocks the entire power transferring system when there is too much current to prevent electrical accidents from occurring.

But oftentimes, these fuses blow up in such a way that it doesn’t block out the electrical system completely, and the remainders of it still make a complete circuit. But that circuit usually isn’t a sturdy enough one, and the jostling from the driving can easily cause it to break, leading to flickering lights.

If your headlight’s fuse has been replaced with a circuit breaker, that can also cause the lights to flicker if your headlights are always drawing amperage which is only marginally enough to trip the circuit breaker.


Check The Relay System of The Headlights

Usually, the headlight relay is located on the fuse panel. If the headlight relay is starting to fail, this causes the lights to switch on and off rapidly.

If your relay has been damaged, see if you can find one that is identical to the relay that’s being used elsewhere in the vehicle’s electrical system, then swap the relays. If you manage to get rid of the flickering this way but develop an entirely new problem elsewhere, then replace the relay.

Do I Need a Capacitor for My Car Audio System?


Install A Power Capacitor

Ways to Fix Headlight Flickering - Install Power Capacitor

If your charging system looks fine, and you don’t want to opt for installing a larger alternator just yet, you might want to try installing a power capacitor. A capacitor helps amp smoothen out the peaks that might appear in the current that your amplifier draws.

Once you’ve installed the capacitor, you’ll surely notice the difference in terms of peaks in the music that causes the power to fluctuate.  Apart from preventing your lights from going dim, a capacitor will also ensure that the volume of the music does not drop suddenly due to a deficiency of power.

But hold on, all this sounds too good to be true, doesn’t it? Here comes the drawback. Well, not necessarily drawbacks, more like a few things you need to carefully consider before getting a power capacitor.

The first one is the size of the capacitor. You need to get one that’s big enough to match your stereo system. This is because different cars have different kinds of audio systems that require different amounts of power. Hence, the emergence of different sizes of capacitors.

The second factor that you need to look out for is the positioning of the amplifier. The closer the amp is located to the capacitor, the more balance of power you’ll get.

Keep in mind that a current takes a bit of time to run along a conductor. The farther away you’ll set up the capacitor from your amp, the longer it’d take for the amp to draw power from it, causing delays in the music, and well, power shortage.


Look For Glitches in The Charging System

If you’ve checked out everything else, but still the flickering doesn’t seem to go away, your last resort is t check if the charging system itself is faulty.

In this case, the only solution left for you to consider is installing a stiffening cap. That should solve any issue you might be facing regarding any glitch in the charging system.


Try Changing Your Headlights

Ways to Fix Headlight Flickering - Change Headlights

By ‘change’, I don’t mean getting rid of the old headlights and getting brand new ones of the same type. Rather, change the type of headlights that you use in your car. The type of lightbulbs used inside the headlights of cars is usually incandescent lights.

These lights use a filament that’s poured inside a glass bulb. Electricity heats the filament up, and light comes out. The main problem with these bulbs is that it requires a lot of power to heat the filament up properly for the lights to shine brightly enough.

But, if you use LED lights instead, the lights send an electric signal through the diode. A diode is a semiconducting material that emits the photons from the electric signal through an electromechanical process called electroluminescence.

The bottom line? LED lights draw much less power than incandescent ones, and shine much brighter, for a much longer period. If you have a shortage of power in your car, the best option of lights for you is without a question, LED.

How to Power a Car Stereo with a Battery Charger?


Final Thoughts

To sum things up, the lights in your car licker when the bass cranked up due to a shortage of power.

You can tackle this problem in many ways. By either balancing out the power distribution from your charging system and distribute it accordingly to different components in the car that draw the power, or by simply adding a more powerful charging system or strengthening the existing one.

You’ll know best which one matches the best with your car and convenience. The main purpose of this write-up was to inform you of the suitable options. The rest is up to you. Hope this helps.