The radio circuit typically uses a low to medium amperage fuse, often in the 10A to 20A range, depending on whether it powers only the head unit or includes an external amplifier. Always cross-reference the color and the stamped number with the specifications provided on the fuse. How to Determine Fuse Size for Car Audio? Before diving into how to select the right fuse size, it's essential to grasp some basic concepts about fuses: Ampere (A): The unit of measurement for electrical current. Fuse Rating: The maximum current a fuse can handle before it blows or breaks the. Which fuse is for the radio in a car? It's usually labeled “RADIO,” “AUDIO,” “ACC” (Accessory), or “CIGAR” in your car's fuse box. Despite being compact, it offers serious current handling, ensuring your setup stays protected without cluttering your install. Blade (ATO/ATC) Fuses – Everyday System Safety Common in most cars, blade fuses are easy. There seems to be a lot of questions regarding fuses and fuse sizes lately. Here are some helpful hints in the process to find the right fuse for you. ) Determine your wire size's max. A lot of people run 1/0 so. Installing the correct size of fuse is just as important as having one in the first place, so let's go over some fuse basics, and then we'll explain how to choose the correct size for your car audio installation.