A quick tip for hooking up
electronics.
Any place that has a connector, used or not, spray with a dielectric grease. If you have a plastic or rubber cap for unused plugs, use it.
It penetrates and
seals the metal from
corrosion and also
seals the case against moisture intrusion.
Using this trick, my handheld
garmin has survived several years mounted on the
deck of my kayak! Still going strong.