Installing an aftermarket radio in your car can lead to a variety of electrical issues. But what exactly are those problems, and how can you fix them?
In this blog post, we’ll cover five of the most common electrical issues caused by aftermarket radios and offer tips on how to avoid them occurring in the first place.
An aftermarket radio can cause electrical issues in a vehicle, such as drawing too much power from the system, interfering with the ECU and even activating a check engine light, creating shorts if not properly grounded, and interfering with other electrical features like headlights, interior lights, chargers, etc.
Key Takeaway
5 Common Electrical Problems Caused By Aftermarket Radio
- Drawing too much power from the car’s electrical system
- Interfering with the vehicle’s ECU, causing a check engine light
- May cause electrical problems due to not being properly grounded
- Electrical problems due to not being compatible with the car’s electrical system
- Flickering lights and other electrical interference due to low-quality radio
5 Common Electrical Problems Caused By Aftermarket Radio

Have you recently installed an aftermarket radio in your car and noticed some electrical issues? Here are 5 common electrical problems associated with installing an aftermarket radio:
1. Drawing too much power from the car’s electrical system

Aftermarket radios are a popular upgrade for many car owners. Unfortunately, these radios can sometimes cause electrical problems.
One common issue is that aftermarket radios draw too much power from the car’s electrical system. This may result in dimmed headlights, flickering dash lights, or even engine stalling.
In some cases, installing an aftermarket radio may even damage your car’s battery or alternator. If you’re having electrical issues after installing one, the initial step should be checking all wiring connections to make sure there are no exposed wires.
Also, ensure to use the correct size fuse for the radio. If still no luck, professional installation by a qualified technician may be necessary.
There are a few possible explanations why an aftermarket radio may draw too much power.
First, the unit could be wired incorrectly; for instance, if the + and – terminals are reversed, for instance, then it will draw twice as much as expected.
Second, older radios often use less efficient designs which weren’t intended to work with modern cars; finally, higher quality units require more energy consumption than factory-installed units do.
2. Interfering with the vehicle’s ECU, causing a check engine light

Check engine lights can be one of the most frustrating experiences for car owners. Not only do they indicate something is amiss with your vehicle, but they’re also difficult to diagnose.
In many cases, the cause of the check engine light is an easy fix; however, there may also be more complex issues at play.
Many car enthusiasts enjoy customizing their vehicles with aftermarket radios, but sometimes these modifications can lead to electrical issues.
One common issue that could occur when installing an aftermarket radio in your car is interference with the ECU of the vehicle – this may be caused by loose connections or faulty ground wires.
In certain vehicles, an aftermarket radio can cause the check engine light to illuminate if not installed correctly.
This occurs because the radio may interfere with your vehicle’s wiring, leading to issues with your electrical system.
In some cases, an aftermarket radio may not be compatible with your vehicle’s electrical system. If this occurs, it’s essential that you get your vehicle inspected by a qualified mechanic to prevent further harm to its electrical components.
3. May cause electrical problems due to not being properly grounded

Grounding a car radio is just as essential as selecting the correct speakers. Without an effective ground, electrical noise can interfere with the signal from the radio, leading to static and other issues. Furthermore, poor grounding may damage sensitive electronic components.
Improper grounding when installing an aftermarket radio can be a serious issue. Without proper grounding, the radio may cause interference with other electronics in the vehicle and even lead to overheating of the unit itself.
Additionally, improper grounding can lead to static electricity build-up that could damage the radio’s circuitry. To avoid these issues, be sure to have the radio installed by an expert who knows how to properly ground it.
The most popular method to ground an aftermarket radio is by running a wire from the chassis of the car to the ground terminal on the back of the radio. This will create a secure connection between them and reduce interference.
Another alternative is using a grounding block, which attaches to the chassis and provides multiple connections for grounding wires.
This may be useful if other electronic components in the car require grounding too. No matter which method you opt for, make sure it remains secure and free from corrosion or rust.
4. Electrical problems due to not being compatible with the car’s electrical system

Aftermarket radios are a popular upgrade for car owners. Unfortunately, some of these radios may cause electrical issues. Many aftermarket models may not always work in sync with your vehicle’s electrical system, leading to flickering lights, strange noises, or even complete electrical failure.
Some problems can be remedied with the installation of a fuse or other simple modifications. Unfortunately, in other instances, the only solution may be to replace your radio with one compatible with your car’s electrical system.
To comprehend why some aftermarket radios are incompatible with your car’s electrical system, it is first necessary to comprehend how that system functions.
The car’s electrical system converts engine mechanical energy into electrical energy that powers all essential elements like lights and accessories in your ride.
However, not all aftermarket radios use the same type of electrical energy. Some utilize direct current (DC), while others rely on alternating current (AC).
Since most car radios are designed to run off DC power, installing an AC-powered radio could potentially wreak havoc with your vehicle’s electrical system.
Incompatible radios can drain your battery, overheat wiring and even start fires. Thus, it is essential that the radio you select is compatible with the car’s electrical system before beginning installation.
5. Low-quality aftermarket radios

Cheaply manufactured or improperly installed aftermarket radios can lead to problems with the car’s electrical system.
Signs of these issues may include flickering lights, radio interference, and unexpected battery drain. In many cases, these problems are fixable by simply replacing the radio with a better-quality unit.
However, if the electrical system has been damaged, professional repairs or replacement may be required. It’s essential to be aware of potential issues caused by aftermarket radios before making any modifications to your car’s electrical system.
Can Installing a Radio Mess Up Your Car?

Installing a radio in your car may seem like an easy enough task, but improper installation can lead to numerous issues. Drilling into the dashboard creates unsightly holes and makes reinstalling the original radio difficult if you ever decide to sell your car.
When installing a new radio, it is essential to make sure all wiring is connected correctly. Otherwise, this could lead to multiple issues such as shorts circuit and electrical fires. Furthermore, an improperly installed radio consumes too much power and strains the car’s electrical system.
Running new wires through the interior of a car can pose trip hazards and damage other components if not properly secured. Furthermore, unfastened wires could rattle against other parts of the car, creating annoying noise and vibration.
Before installing an aftermarket car radio in your dash, be sure to weigh the advantages and drawbacks. It may be better for you just to enjoy music from your phone instead.
What Happens If You Don’t Ground a Car Stereo?

Most car stereos will function just fine without grounding, but there can be some potential issues that could occur. One such issue is that the sound quality may not be as good as it could be if the stereo were properly grounded.
Another potential issue is that static electricity build-up could damage your car stereo. To prevent such issues, grounding your stereo is recommended; not only does it protect it from static electricity damage but it also enhances sound quality.
When grounding a car stereo, there are a few essential things to remember. First, ensure the ground wire is connected to an unpainted metal surface for optimal connection and corrosion prevention.
Second, use sandpaper or a wire brush to scrape away any paint or rust from the surface. Doing this will help guarantee an adequate connection and prevent your ground wire from coming loose.
Finally, make sure the ground wire is connected to the frame of your car rather than just its body. This will reduce electrical interference and guarantee a more dependable connection.
With these tips in mind, grounding a car stereo should be simple and stress-free.
How Many Watts Does an Aftermarket Radio Put Out?
Most aftermarket radios output between 14 and 18 watts RMS, with some higher-end models offering up to 22 watts RMS.
On the contrary, car radios typically only output between 4 and 6 watts RMS, so if you need more power from your radio, an aftermarket model is likely your best bet.
Be mindful that more power does not guarantee better sound quality. Unfortunately, many car stereos with high wattage ratings often sound harsh and distorted.
Therefore, make sure you do your research to ensure you purchase a top-tier stereo before making your purchase.
Aftermarket radios offer more features and superior sound quality than factory-installed radios, giving your car a personal touch.
However, before installing an aftermarket radio in your car, make sure its electrical system can handle the additional load.
Most aftermarket radios require more power than their factory counterparts, and if your car’s battery is already struggling to keep up, adding an aftermarket radio could be too much for it to handle.
If you’re uncertain whether your car’s electrical system can support an aftermarket radio, consult with a professional who can assess your car’s needs and help select one that won’t overload it.