Dose the car need to be on 4 the radio to work.on the audi a4 2004..
Car radios have two sources of power. One source is on all the time to power the clock and keep the presets. The other is hot when the key is on. Some cars have a delay so the radio stays on for a few minutes after the key is turned off.
In my 2003 A4 Quattro, the radio comes on without the car being on or with the key in the acc position.
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