ok try this to narrow it down... unplug servo from rx now unplug esc from rx plug esc into servos old ch1 slot .see if esc works thru steering wheel...if it does you need a rx or try rebinding rx to radio..
Hi.. do you have the xl5 esc?. if yes check the bullet plugs inside the clear shield on the red and black wire then wiggle the red and black wire might be a loose solder joint either on motor or esc