how long can the battery be disconnected before losing presets?
As soon as the negative (-) battery cable is disconnected. But you can buy a memory saver device that plugs into the lighter or power port to save the radio presets and clock. We have them at NAPA. I'm sure other stores sell them as well. HTH. -Jim
Sometimes my car will hold the settings for a few seconds but buy a device that allows you to hook up a 9v battery to your cigarette lighter.
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