Door Ajar light on

I have a 98 plymouth Neon, the door ajar light is been on since I had a CD player instaled, somtimes, the dome light goes on for a while. I am a bit concern about the battery going low in winter. Please help me. Thank you in advince.

Pull the fuse for the cd player and see if there is any change. (It’s possible a wire got crossed or damaged during installation)

If the problem is corrected (which you will realize when you pull the cd fuse), return to whomever did the cd player installation and have them search out the fault.

If it turns out the fault is not with the cd player, you might want to spray some electrical contact cleaner into the courtesy light door plunger switch and work it for a bit to get the cleaner inside.

The door ajar light may be on due to the door not closing tightly which in turn can cause the dome light to come on. Check that the door striker plate is adjusted properly.