Hi,
How long did the starter stay engaged until you were able to disconnect the battery?
I attached a schematic of the starter system. I circled the fuse I believe you are referring to as well as the purple wire on the starter. The first thing I want you to try is to disconnect the purple wire from the starter (S terminal), make sure the wire is shielded so it can't short, and then replace the fuse and see if it blows.
Do this and let me know what you find. Also, when you look through the wiring schematic, you'll see there really isn't a lot to go bad. However, if the starter was engaged long enough, something may have melted and shorted causing the new problem.
If the fuse doesn't blow when the key is off, then I suspect the main power supply to the starter is okay. That leaves the purple wire that gets power through the transmission range sensor from the ignition switch. My guess at this point is somewhere in that wire is a short. Also, make sure nothing in the fuse box itself was damaged.
Take care and let me know what you find or if you have other questions.
Joe
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Friday, September 4th, 2020 AT 7:59 PM