Module for car lights

Hello. I have a question about a car module. Can anyone help me with a scheme for a module which will activate my lights when I unlock my car. I am not looking for a coming home/leaving home module with its own time, as my interior lights come on when i unlock my car and go off when locked so I would use them as a trigger. So basically I need a module which will have constant positive (+) provided to him and it should be triggered by negative (-) charge.