I was in my garage repairing a harness I bought off ebay (in "good" condition) last night. About midnight I got around to bench test the double relay... completely frozen on one side. After checking the price of a replacement I decided to try to tackle it. One coil was totally rusted over and the tiny spring that opens the contact was just a lump of rust. To my surprise, the whole thing cleaned up pretty easily! These things are really bullet proof! Definitely recommend trying to repair before you buy a new one. Click to view attachment

....Yes that is a good thought ....also a little,
very little electronic contact cleaner as a preservative.