I have fixed a problem with the hatch opener and the interior fan not functioning by re-seating the relay in it's place on the fuse panel under the dash. Now however, the same problem has occurred again. The hatch can still open by key, and the interior fan is not mission-critical, so I am considering a brand new relay or pulling it to disassemble and check the contacts and spring function. After 30+ years it's probably time for a new relay.
[Dec 2019 Update] After seating a second time and replacing a worn radiator hose, the system while running hot in stop and go traffic, is remaining cool during highway driving.
