Husbands jettas battery has been dying. .he says radio stays on after he takes key out.
It sounds like you have the radio connected wrong or a short in the electrical system. The radio may not be the only component getting power with the key off, and these components being on will drain the battery within a few hours or less. If you would like to have this checked, a certified technician, like one from YourMechanic, will be able to conduct electrical testing to determine the exact cause of your battery issue.
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