Fuses are essential elements which protect both home and car stereo amplifiers from damage. Fuses are designed to blow if the stereo amplifier receives too much voltage, as the result of a short in the system or an over-voltage surge by the car’s electrical system. If your stereo has quit working, check the power supply for your home stereo by unplugging your home stereo amplifier and connecting another electrical appliance to the outlet. If it works, you probably have blown a fuse. To test your car stereo amplifier, use a voltmeter or test lead to check the power cable leading to the car stereo amplifier. If it has 12-volt power, you may need a new fuse. If the fuse on your stereo amplifier has blown out, be thankful that it has sacrificed itself to protect your amplifier.
