How can I make interior lights on for a few seconds after turning off the ignition off?
Not really much you can do unless your vehicle has that option built in. There is a body control module that operates your interior lights, door locks, alarm system, etc.. It is possible, but then you're talking about finding, identifying circuits and adding time delay relays. Or do some research and maybe it's possible to have the control module reprogrammed? I'm not too sure about that though.
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