What is the current of the car's built-in USB?
2 Answers
USB1.0 and 2.0 have an output voltage of 5 volts and a maximum current of 0.5A. How to use USB: Insert the USB into the car's USB port. Turn on the device power to use it, and you can also copy MP3 music from a computer. Precautions for USB use: The USB drive requires driver loading during use. If the USB drive or phone is occasionally not recognized, try reconnecting it. If the USB drive is not used for a long time, remove it promptly to prevent accelerated aging of the USB drive, as the host system frequently reads and writes to the USB drive, affecting the host's operating speed. Keep the USB port clean and tidy. If there is corrosion, water stains, small debris, or other foreign objects in the USB port, it may cause the USB drive to fail to connect properly.
The built-in USB ports in cars usually have a small current output, typically around 0.5 to 1 ampere, which is the standard configuration. Through my experience in vehicle maintenance, I've found many car owners complaining about slow charging speeds. The USB ports are designed this way to protect the vehicle's electrical circuits and prevent overload issues. The voltage is fixed at 5 volts, and the current level affects charging efficiency. Some older cars only support 0.5A, which is sufficient for charging phones but inadequate for powering devices like tablets. Newer vehicle models may come with USB-C ports capable of delivering 2A or higher current, supporting fast charging. During inspections, it's advisable to use professional tools like a multimeter for accurate measurements; a current below 0.5A might indicate a loose or aged port. For daily use, don't expect it to quickly charge large devices—it's better to install a cigarette lighter adapter for more powerful current. Safety-wise, the current limitation reduces the risk of short circuits. In summary, low power output from car USB ports is common, but upgrading accessories can enhance the experience.
