# The Hidden Danger of Car Adapters: How Cheap USB Chargers Can Ruin Your Vehicle
If you’ve ever used one of those small USB adapters plugged into your car’s cigarette lighter or aux port to charge your phone or run a device, you might want to think twice. According to auto mechanic and YouTuber, this seemingly harmless little device can cause significant damage to your car’s electronics through electromagnetic interference (EMI). In this article, we’ll dive deep into how these adapters work, why they’re problematic, and what you can do to protect your vehicle.
## How Car Adapters Work
Most of us assume that these adapters are simple devices designed to convert the car’s 12V DC power to a 5V DC charge for our devices. But as explained in the video, it’s far more complex than that. When you plug one into your car, it takes the 12V DC power and uses a solid-state system to switch it into high-frequency AC voltage. This AC voltage then passes through a coil, diode, and capacitor to become 5V DC for your devices.
While this process works perfectly in a well-engineered adapter, cheap models often cut corners. They may produce too much AC voltage, which can radiate throughout your car’s electrical system and interfere with critical components like your keyless ignition or tire pressure monitoring system.
## The Problem of Electromagnetic Interference
Modern cars are a complex network of computers, sensors, and radio frequencies (RFI). Everything from keyless entry to automatic braking relies on precise communication through these systems. Unfortunately, the high-frequency AC voltage produced by many USB adapters can interfere with these signals, leading to unexpected behavior or even complete system failure.
One example shared in the video is a Subaru Outback that wouldn’t start because four of these adapters were plugged in simultaneously. When they were removed, the car started immediately. The mechanic also mentioned encountering issues where airbag codes and tire pressure monitoring system codes were triggered due to RFI interference from these devices.
## Why Cheap Adapters Are Risky
Cheaper adapters are often sold at gas stations, hardware stores, or even drugstores. While they might seem like a bargain, their internal components are not up to par. They can generate excessive AC voltage that interferes with your car’s electronics and may not have proper fusing to protect against overloading.
Overloading the system is another issue. Plugging multiple devices into a single adapter or using one that’s rated for too low an amperage (like 2A) can cause it to melt or fail, potentially damaging your car’s electrical system in the process.
## Solutions: How to Protect Your Car
1. **Invest in Quality Adapters**
The video recommends spending around $20 on a reputable adapter like a Qualcomm one. These higher-quality adapters are less likely to produce excessive RFI and come with better safety features, such as proper fusing and lower electromagnetic interference output.
2. **Use a Power Inverter**
For serious electronics use, the mechanic suggests using a power inverter that connects directly to your car’s battery. This bypasses the vehicle’s electrical system, providing clean power without risking EMI-related issues. These inverters can supply more power and are ideal for running high-draw devices like laptops or even refrigerators.
3. **Wrap Adapters in Aluminum Foil**
As a temporary fix, wrapping your adapter in aluminum foil can help contain the RFI emissions. While this isn’t a long-term solution, it’s an easy way to test if EMI is causing issues with your car’s systems.
4. **Unplug and Test**
If you suspect EMI is messing with your car, try unplugging all adapters for a couple of days and see if the problem goes away. Computers in modern cars continuously monitor for issues, so if the problem clears up within a day or two, it’s likely due to the adapters.
5. **Avoid Overloading**
Only use one adapter at a time and avoid plugging in too many devices on a single port. This reduces the risk of overloading your car’s electrical system.
## The Future of Car Power: Why It Matters
As cars become more reliant on advanced electronics, understanding how external devices interact with their systems becomes crucial. While most modern vehicles are built to handle some level of interference, cheap or poorly designed adapters can still cause unexpected problems. By taking a few precautions and investing in quality products, you can ensure your car stays safe and runs smoothly.
## Conclusion
The next time you reach for one of those small USB chargers, think about the hidden risks they pose to your vehicle. While they might seem like a convenient solution, their potential to cause EMI-related issues is real and can lead to costly repairs or even safety hazards. By choosing better adapters, using inverters, and being mindful of how you power your devices, you can protect your car from this invisible threat.
If you want to avoid these problems altogether, consider upgrading to a high-quality adapter like the one the mechanic recommends—a small investment that could save you from bigger headaches down the road.
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**Giveaway Alert!**
The YouTuber is offering a chance to win a high-quality Qualcomm USB adapter for free in this video. To enter, simply leave a clean, non-offensive comment on the YouTube video and let the system randomly choose a winner. Don’t miss your chance to protect your car’s electronics while enjoying reliable power for all your devices!
"WEBVTTKind: captionsLanguage: enRev up your engines,now it's come to my attention recently byfixing customers cars, that these little adaptersthat you put in your car to run anything likeyour phone or a computer that are 5 voltsthat plug into the cigarette lighter or youraux power, they can cause problems in yourcar that you would have never thought, andthey do it through the process of electromagneticinterference, you can't see it and let's faceit even the physicists don't really understandelectromagnetic stuff it's even beyond themwhen it comes to how this stuff actually works,just like gravity you can't see it but youcan certainly feel it if you jump up, it pullsyou back to the planet, well electromagneticinterference on a modern day car can do allkinds of damage, so I'm going to tell youhow you can keep that from happening withthese little adapters in your car, now moderncars have everything run by computer, electricity,magnets, and a lot of the system are evenusing rfi using radio frequencies, like yourkeyless ignition if you have that, the keylessignition sends a radio frequency to your carand says it's ok to start it up, well guesswhat these little babies put out some radiofrequency too, now these little adapters maylook simple but their actually not, to beginwith you plug them in, they take the 12v dcof your car and uses solid state system thatswitches the dc voltage of your car into highfrequency ac voltage, then that ac voltagegoes through a coil, a diode, and a capacitorto become 5 volt dc, it's a lot more complexthan you might of thought this thing is, nowif done correctly it works perfectly fine,but as everyone is aware, you can get dirtcheap models of these, you can get them ata gas station, a hardware store, I've evenseen them in a drug store, but it's not agood idea to buy one of those cheap ones,as I just explained their pretty complex inside,if they have cheap parts, maybe they makea little too much ac that's broadcast allthrough your car and can mess things up, andyou certainly don't want to overload yoursystem using too much on one plug, this hastwo I advice only one, I've seen some thathad 4, and you don't want to buy a cheap one,I personally use a qualcomm one, hey it'slike $20 it's not that big of a deal, butI don't advise going and buying $8 or cheaperones, and don't overload the amperage ratings,where your plugging it in or for the deviceitself, I've had customers plug these in andput some laptops and stuff on them, they'veactually started to melt these things fromtoo much amp draw, take this cheap one here,it's only rated at 2 amps, so you put moreamperage on that you can cause problems, nowthe worst problem I ever saw was on a customerssubaru it was an outback it has a bunch ofplugs the kids were always running stuff,one day they got in the car and it wouldn'tstart, so they towed it in and I hooked upmy scan tool and couldn't find any problems,but since I realize these things can causeyour car to get weird, I look in the car there's4 of these things plugged in all over theplace, so I thought let's do a little sherlockholmes, I went through the car and I unpluggedthem all out of the adapters, then since itwas a keyless ignition I didn't have to turnthe key I already had that in my pocket, Ijust went to push the start button and guesswhat it started right up, the radio interferencecreated by this little thing that turns thedc to ac and then back to lower dc, was interferingwith the signal between the key and the computerand it wouldn't let the car start, I've seenit trip airbag codes, when I scanned it, itdidn't show any codes, so I saw the same thingthere were a bunch of these adapters pluggedin, reset the computer and I drove it aroundand the code never came back and months laterthey said it never came on again, we don'tplug all those things on anymore and we tookyour advice and bought more expensive oneswhen we are using them, I've seen cars whereautomatic tire pressure monitoring systemwas tripping codes, now that makes total sensecuz this is broadcasting rfi, and tire pressuremonitoring systems, each valve stem is broadcastingradio frequencies into the car to tell whatthe pressure of the tires is, these were interferingwith it, because when you think about it theseare kind of a stop gap measure, you plug theminto an adapter or something, if your reallyserious about electronics what you reallyneed is get yourself one of these power invertersand hook it directly to the battery, becausewhen you do that your going directly off thebattery, your not tapping off the wiring systemof the car that can create problems, thenyou have whatever power you want, this onehas a couple of usbs and 100v ones you canplug stuff into, these are for serious electronicuse, wire it to the battery like I say andyou can put this under the seat and put itwherever you want, then you have a good supplyof power that isn't going to mess with anything,because modern cars with all their wiringand computers, I've seen a lot of kids they'llput in a fancy stereo system in their car,and they'll just go under the dash and they'llfind a power wire that has power when theyturn the key on and they'll start wiring stuffoff of that, you can destroy computer systemsdoing that, if your real serious about powerin your car hey put an inverter in it thenyou can have all the power you want runningdirectly off the battery with it's own fusegoing to the battery so your not taxing theelectronics of the car in a way it wasn'tdesigned for, when I had a customer who washaving a problem and I unplugged it and itwent away I thought I wonder if you can stopthe rfi interference from coming out, so Ijust got a little aluminum foil and I rappedit around the thing, well that was enoughto keep the waves from escaping and it didn'thave the problem anymore, so if you want torap any kind of insulation around these thingsit's going to stop most of the radio interferencefrom being broadcast out of the thing, butI've also found that I had no problem in anyof my cars cuz I buy a quality one that hasone tap coming out not two or three or four,I use this qualcomm one and like I said it'saround $20 they seem to be a lot better madeand they don't put out as much rfi as thereally cheap ones do, and of course realizethat if your powering devices with these thatthey themselves put out radio waves in thiscase microwaves, that can eventually causea problem if you've got too many people usingtoo many phones, too many other wireless devicesin the car it can make strange things happen,cuz you can't see electromagetism unless youhave a strange brain and senses inside it,it's out there doing it's thing 24 hours aday whether you know about it or not, so ifyour car does seem to be acting weird, heyunplug ever single one in your car for a coupleof days and drive it around, cuz computershey their always checking for problems inyour car as you drive, if that's the problemand you take it out, within a day or two ofdriving, let's say your check engine lightis on or something, if it goes away it cando that automatically and you will know thatit was these things putting radio interferenceand messing with your car's electronics, andif your car is older and doesn't have builtin usb ports get one of these inverters, thisthing is good enough to run a refrigerator,it will certainly run anything they've gotgoing in the back seat, and since this ismechanic monday I'm going to give away oneof these qualcomm adapters that doesn't createproblems, to have a chance to win just placea clean non offensive comment on the youtubecomments below and a winner will be chosenrandomly by computer to get a high qualityqualcomm usb adapter so you can use your devicesto your hearts content and not worry thatit's messing with your car's electronics,so if you never want to miss another one ofmy new car repair videos, remember to ringthat bell\n"
