ElWhino69

I appreciate all the help and after following all the advice, I've now got 36V output to my TM. I did, however, run into something that I didn't expect. The trolling motor wires coming into the back of the boat had 2 red wires and 1 black wire. There are two 50amp circuit breakers in the battery compartment. One of the red wires is connected to a CB and a red wire comes out of the other side. This wire has markings for connections to Battery #1 positive which makes sense. The other red wire connects to one side of the second CB and and has a red wire coming out of the other side that is clearly marked for connection to Battery#2 positive. My trolling motor harness from the foot pedal to the receptacle only has a red and black wire, however the underside of the receptacle has both red wires running into it. So the 2nd red wire is a mystery and I would appreciate any comments. I'm attaching a picture of the male plug from my trolling motor foot controller and I noted it's stamped with 30 amp, 125V.

I'm trying to hook up 3 deep cycle batteries on my 2003 TR19 but I do not know the connection sequence. I had a guy hook them up for me but the output is only 12v not 36v. I'm attaching pics of the current connections. I would appreciate any help I can get with this.