radio does not turn off
It might be a defective system. If you bought it from a Ford dealership I'm sure they'd replace it.
Sound like it is wired to a 'live circuit'. A 'live circuit is one that always has power when the ignition switch is OFF. But with modern radios I agree with BuiltTough. It is defective or the door open circuit has ben detached to it. Previous to (I think) 2002 radios were attached to switched circuits where the ignition had to be at ON or ACC to feed power to the radio. Modern radios are hooked to live, and are supposed to shut off when you open a door. If still under warranty take it to your Ford dealer. If not, follow the lines to the fusebox. If someone added an accessory, like XM radio, it may be holding the cirucit open. see http://www.mustangcollective.com/showthread.php?t=26033
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