'92 Corsica 3.1 warning chime and speedometer drop after turning off

[automan9482]

Purchased a 92 Corsica 3.1 V6 A/T to flip. Not a bad car generally, but right away the cooling fan didn't work. I checked the fuses, jumpered the fan itself (good), then the relay (connector jumpered fine & fan worked), then replaced the relay with a known good one. Cooling fan still didn't work, so I hot wired it to run continuously when the key is on by splicing the pink/black and black/red wires together, which worked fine with no issues.
What does this have to do with the problem in the title?
Suddenly, now when the key is turned off, whether the engine is running or not, there is a 5 second pause, then the interior warning chime "Dings" once, and the speedometer needle drops from 0 to the 6 o'clock position. It floats back to about 7 o'clock and stays there until the key is turned back on. When the key is turned back on, the speedometer needle jumps back up to 0. Nothing else is funky electrically, everything works fine otherwise, and the car runs and drives fine. It didn't start doing this right away after splicing the fan wires, so I don't know if that is relevant.
Any thoughts?

[automan9482]

This part of the problem is fixed, at least. Undoing the hot-wire splice on the cooling fan relay and re-splicing it as originally designed took care of the chime and speedometer drop after shutting off the ignition. Soooo, hot-wiring the fan will not solve my problem.
However, the cooling fan still doesn't work by itself. Please view next post.