Removing the plug connectors isn't that bad on the switch side. BCM side is a little more difficult.
Use a small pick or screwdriver to depress the silver tab and they slide right out.
On the CLP side you can take apart the shell and then use the same procedure to inspect the connections for any corrosion from water. I haven't tried this yet on the CLP, but but I have been able to save some water damaged connections this way with some salt and vinegar then re-tin.
For the main switch body there are 6 screws and the cover just comes off to show the circuit board. Easy to visually inspect for any burnt traces or get a meter on them at that point.
Let me get some pics for you if you are interested.
I have the same issue with my spoiler switch so maybe we can solve this together?