Weak connections and battery can be the route of all electrical gremlins/evils.
Have your battery load tested with a good tester. Luckily I have a local shop that has a Midtronics exp 800 hand held load tester. My 800 CCA Delco battery read like 440 CCA and low on voltage, I had all kinds of gremlins then.
I installed a sealed Odyssey PC-1500 DT and used the top posts for better connection.
This battery load tested new at 1219 CCA!
Load test: Midtronics EXP800
Let there be real power and you will never get corrosion on terminals with this battery, and if your battery is under the rear seat you wont have any venting into cabin from this sealed absorb glass matt technology battery.
Odyssey is the best ,I expect 10-12 years of service life from it.