Ok, now I know I don't understand electricity or how a multimeter works. I test the fixtures like you suggested. I didn't get any kind of reading I understood. I clean all the contacts with distilled water before checking the leads and LED's. We did find a couple of loose ground wires. I also have several of these which are rusted badly. See images.
I would really appreciate it you could come to the house and take a look, of course when it convenient for you.
Thanks
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