now you know everything is new, so that was not the problem, you will have to troubleshoot the others.
forward / reverse switches and potentiometer, harness. at the multi handle
at one time i had a loose connection at the Pot meter, under the handle, sometimes it make good contact sometimes not
i replaced the Pot meter and solder the wires, problem solved, just to give an idea
wishing you success
This is ONLY to be used to report flooding, spam, advertising and problematic (harassing, abusive or crude) posts.