There will be two and possibly three fuses. After connecting the battery or jumper cables backward, you can expect to have a lot of blown fuses. Check all of them under the hood and inside the car. One fuse is typically listed as being for the radio, but there will always be a second one for the station preset and clock memory that is tied in with some other circuit that is always on. The interior lights is the most common circuit, but it could also be the horn, brake lights, or cigarette lighter.
A lot of import radios also have a fuse plugged into the back of the unit. You have to pull the radio out to find those.
If the radio is still dead, unplug it and use a test light to measure the voltages on the terminals in the connector. There must be one with 12 volts all the time. A different one must have 12 volts when the ignition switch is on. If either one is missing, you overlooked a fuse somewhere.
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Tuesday, February 26th, 2013 AT 9:58 PM