hello.bummer did you remove esc red wire b4 turning power on .if you did not thats what caused issue.. remove red wire center wire from esc to rx. it has a small tab on rx plug the contact will then slide out of housing . shrink-wrap that contact and a small amount of wire. try powering on again. not sure this will fix all esc might have been burnt due to the new bec install b4 removing red wire