What are the reasons for a car USB port not supplying power?
2 Answers
Car USB port not supplying power could be due to issues with the USB cable or the charging module. Try connecting the USB cable to a computer; if it works normally, then the charging module is damaged. If there is no response, try another USB cable. If it still doesn't work, the issue might be with the device or the battery. The USB ports in cars are primarily designed for audio data transmission, mainly for playing music via USB drives, etc. Therefore, most vehicle USB ports have a current of only 0.5A, while the standard charging current for mobile phones is 1A. Prolonged charging usage may cause adverse effects. It is recommended that car owners reduce charging usage to provide some protection.
I've encountered this issue several times, and a non-powered USB port is quite annoying. The most common cause is a blown fuse, especially after using the cigarette lighter, as the fuse might not withstand the current and break. You should check the fuse box location, usually under the steering wheel or in the engine compartment, and refer to the manual to identify the USB fuse. If it's blackened, try replacing it. Another possibility is that the USB port itself is loose or clogged with dirt—use a toothpick or cotton swab to clean the port gently, avoiding excessive force to prevent damage. Aging wiring can also be a factor, such as worn-out wire harnesses causing a short circuit or open circuit, preventing power from reaching the port. Additionally, the vehicle's state might be the issue—USB ports may not supply power when the engine is off, so you need to start the car. I once fixed it by simply restarting the vehicle. Of course, if none of these work, just take it to a repair shop honestly; don't tinker around to avoid causing other problems. It's better to have the technician check the USB system during regular maintenance as a preventive measure.
