I left my driver's side window cracked open during a thunderstorm a few nights ago. Luckily I just had a damp carpet. Today, after a thorough inspection to verify it was dry, I "waterproofed" my Central locking unit. I know that ECU Doctors make a
great product and I may go for that in the future, but for today, it was a cheap DIY with hot-glue on the seam and dielectric grease around the connections and fuse:
