I bought my son a used E-maxx. I was converting the battery connections from Anderson to Tamiya. I charged up his new Venom 3000's and plugged the battery in and it sparked and the battery almost immediately started to get very warm. It only does that on one of the battery plug on the right. I don't get any reaction when I plug just one battery in and am afraid I have burned the ESC. Just a little history, earlier I bought a solder gun and was trying to solder the new tamiya wire/plug to the existing wire. Once I realized I didn't have the skill to do it properly I purchased some connectors that you can just crimp. Please help. I don't know if I messed up the esc while soldering or if it could be something else.