why is cab power still on after key is shut off and door is open
...think that perhaps your starter switch is bad....fell off the mountings?~ http://www.rockauto.com/catalog/x,carcode,1440012,parttype,4700
your truck is designed to run accessories like the windows and radio for about 10 minutes after the truck is shut off, or until one of the front doors is opened if sooner. the sensor for the doors is probably bad.
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