Make sure that power and ground aren't accidentally reversed. Double check all connections at the vehicle harness with a test light or preferably a voltmeter. Also, make sure that you are not overloading the power lead. There should be only 10 - 15 amps on a radio circuit. No amps or other adapter/power supplies should be connected to the radio's power leads unless they have a low current draw. Hope this info helps.
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Make sure that power and ground aren't accidentally reversed. Double check all connections at the vehicle harness with a test light or preferably a voltmeter. Also, make sure that you are not overloading the power lead. There should be only 10 - 15 amps on a radio circuit. No amps or other adapter/power supplies should be connected to the radio's power leads unless they have a low current draw. Hope this info helps.