cause. Just disconnect the harness plug and see if the issue goes away. It's the easiest to troubleshoot due to access and may have an issue even if you think it's good.
If the problem continues I'd start with the driver side door just because it's opened and closed the most. Trick the pin switch into thinking the door is always closed (electrically) and see if the problem goes away. If not move on to the hatch and then passenger door. The process of elimination should eventually allow you to find the issue.