24V Minnkota foot controlled trolling motor, no transducer or spot lock.
It was working when I used it, tho I had to clean blue/green corrosion off the receptacle on the boat the first time I used it this season. The cover to that receptacle is broken in half and I guess moisture got in.

I leave for a couple weeks turkey hunting and my daughter borrows the boat. Brought it back, said TM didn't work for them, not for the entire week as I understand. Son-in-law isn't a dummy by any means, replaced the receptacle and plug on the TM with new. But he used two prong stuff, I had three prong. Still not working. Batteries show charged, where do I start on this?

How do I test the TM to see if it works first? Remove receptacle and TM plug and go wire to wire?

If the trolling motor itself tests good, where do I look next? Back to three prong stuff?

I have a Harbor Freight meter/tester to I can check with that if someone give very explicit instructions.
Any help appreciated.