Light Notification Sound Not Working Anymore

I own a 01 Volkswagen Golf. Recently the notification sound that signals that your lights have been left on doesn’t work anymore. This is a big problem for me because sometimes during the day if I turn the lights on, I won’t realize they’re still on and accidentally leave them on and drain my battery. It seems that it’s somehow related to the door ajar sensor which also doesn’t seem to be working. My Check engine light has also been coming on every month or so. When my mechanic plugs the car into the computer, I don’t believe he gets much info on any specific problem. Im not sure if that is related or to this specific problem or not. Any help pointing me the right direction would be appreciated.