Ceiling light comes back on after parking

Lights that fade out slowly is a gimmick that requires a computer, and computers cause more problems than they solve. They do weird things when supply voltage is low, including turning various circuits on, pulsing them, or failing to turn them on when they should. The first thing I would do is measure the battery's voltage a few minutes after stopping the engine. It should be 12.6 volts. If you find less than that, we will need to look at the charging system and if testing the battery is warranted.