Replacing a Cigarette Lighter With USB

USB, AUX and cigarette lighter outlet

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If you’re absolutely certain that you’ll never want to use your cigarette lighter as a cigarette lighter, or even as a 12-volt socket, then yes, it is possible to tear it out and replace it with another accessory like a dedicated USB port. That may even be the best possible scenario for your particular situation, but it’s still worth considering your options first. Since car cigarette lighters are also universal 12-volt sockets that can be used to power anything from a cell phone to a tire pump, you may be giving up more than you gain.

Cigarette Lighters and 12 Volt Sockets

While it is true that the accessory sockets found in virtually all modern cars and trucks started out as cigarette lighters, they’re increasingly used for other purposes. In fact, some cars ship without the cigarette lighter portion at all and instead include some type of safety plug. Other vehicles include a single cigarette lighter socket and then several 12V accessory sockets that won’t even accept cigarette lighters.

The inclination to ditch your cigarette lighter, in light of the fact that you don’t smoke and won’t allow smoking in your car, is definitely understandable. But first, it’s important to note that a cigarette lighter socket can power a lot of different types of devices, which is functionality that you’ll lose if you replace it with something like USB.

For instance, a typical cigarette lighter circuit is capable of providing enough amperage to power devices like phones and tablets, via a USB charger. However, you can also plug in a higher amperage device like a 12V tire pump, many of which are designed to draw little enough amperage that they won’t blow a cigarette lighter fuse. You can also plug in a cigarette lighter inverter and power other electronics, provided they don’t draw too much amperage. Other accessories, like car air ionizers and purifiers, can also be plugged into your cigarette lighter. Devices that draw more than 10 or 15A will typically require a hard-wired inverter.

Replacing a Cigarette Lighter With USB

The easiest way to replace a cigarette lighter with USB is to just toss the lighter portion and plug in a low profile 12V USB adapter. Some 12V USB chargers are big and bulky, but there are a number of options that fit more or less flush with the dash and come in a variety of colors to better match the trim. This option will leave your cigarette lighter in place as a 12V accessory socket, just in case you ever want to plug in a tire pump or anything else that can’t be powered by USB. Done correctly, it will also result in a clean installation that gives the impression that you have ditched your cigarette lighter in favor of a USB port.

The other option is to remove the cigarette lighter socket and install a USB port in its place. This is also a totally viable option, and there are a ton of aftermarket options out there. Some provide two USB ports in the same space occupied by the old cigarette lighter, while others include other functionality.

Replacing a cigarette lighter socket with a 12V USB port is a relatively simple operation, but you may have problems with fit and finish. Although more or less direct replacements do exist, you may have to cut into your dash a little or do some finishing work to make everything look clean once you’re done.

Wiring a 12V USB port in place of a cigarette lighter socket is a simple matter, once you’ve found one that will fit in your car. The cigarette lighter socket will have positive and negative leads, which you’ll have to disconnect from the socket and reconnect to the USB port. Depending on the way the socket is wired in, and the terminals built into the USB port, there may be some cutting and soldering of wires and terminals involved.

Limitations of Replacing a Cigarette Lighter With USB

If you decide to remove your cigarette lighter and wire in a new accessory like a USB charger, it’s important to remember that the new accessory will have the same limitations as the original socket. Since you will most likely end up using the existing power and ground wires, the new USB accessory won't be able to pull any more current than the original cigarette lighter socket without blowing a fuse.

It’s also important to note that while you can replace a cigarette lighter with USB, you can’t just wire a USB port into the existing cigarette lighter power leads and call it good. USB is designed to provide 5V DC, while your vehicle’s electrical system provides somewhere in the neighborhood of 12V - 14V. Accessories that are designed to replace a cigarette lighter with one or more USB ports include internal circuitry that allows them to provide the correct voltage to your phone and other electronics.

Exploring Other Cigarette Lighter USB Options

Directly replacing a cigarette lighter with a hard-wired USB port accessory is a great option if you’re looking for a really clean, OEM-type look without any messy wires. However, leaving the cigarette lighter socket in place and installing a flush mount USB charger opens up a lot of other options down the road.

Most hard-wired 12V USB accessories that are designed to replace a cigarette lighter socket only provide a single USB port, or two at the most. Similarly, most low-profile USB chargers that you’ll find only provide a single USB port. This is fine if you’re the only one in the car, but if you ever want to provide power to one or more passengers, it could end up problematic.

By leaving the socket in place, and using a low-profile USB charger for a clean look, you leave open the option of pulling the low-profile charger and plugging in a multi-tap should the situation ever call for it. Some cigarette lighter socket multi-tap devices provide four or more 12V accessory sockets, in addition to USB ports, which can push right up against the amperage capabilities of the cigarette lighter socket while providing power to all of your passengers simultaneously. These devices don’t look as clean as a low-profile charger, or a hard-wired USB accessory, but you can always stash them away under the seat or in the glove compartment when not in use.

Another option is to replace the cigarette lighter with a pass-through device that hooks into your head unit. This type of device doesn’t connect to the preexisting wiring from a cigarette lighter, so that will have to be safely snipped and taped to prevent a short.

Instead, this type of device will include a USB port and a 3.5mm aux port on the front, and cables on the back that you can plug into your head unit—provided your head unit has auxiliary inputs and a USB connection on the back. This essentially provides an auxiliary input and USB connection conveniently located in your dash or center console without having to cut any additional holes.

Cigarette Lighters Versus USB Power

Regardless of the way that you decide to go with your cigarette lighter socket, either working around it or totally replacing it, you’ll definitely get a lot of use out of USB on the road. Most portable devices today can be powered by USB, and it’s also increasingly found in head units as a way to transfer data from phones and MP3 players.

Leaving the cigarette lighter socket in place may provide more options today, but USB probably has more legs in the long run. With smoking out of vogue, ashtrays have been disappearing from cars and trucks since 1994, and cigarette lighter sockets could very well be the next on the chopping block.