The heat that wears down the connectors usually is the connectors that tie the electric cabling to the heat element. So look inside and see where the element is coming thru the cabinet out side of the cabinet where you saw the element come thru is where you need to be looking.
Also, are you using an extension cord? If so, try plugging directly into socket.
Try cycling the controller, Plug in you MES, turn on via controller, next set a temp & time, wait a minute or two, now turn off the MES using the controller on;/off. Unplug the MES, wait about a 30 sec or 60, plug back in, go thru the above procedure. Do this 3 or 4 times, pay attention to the light that tells you if the element is on, check the element and see if any heat at all. Still no joy, call
Masterbuilt and ask them to help troubleshoot the problem.
There are parts from a variety of manufactures (heat elements, controllers, senors, etc. ) however none are a direct replacement. If your controller is dead, then you can either buy a new MES controller or upgrade to a PID controller.
Personally I bought my MES because it is a solid smoking platform, if a part fails forget
Masterbuilt and find a replacement, you might have to make a mod or two, but you should end up with a better smoker.