I have the same problem. When using the 5v jumper for the Bltouch the 1.6 ramps burns the 5v voltage regulator of the mega arduino, so it no longer works with 12v on the shield. To find out if you have damaged anything else on the arduino mega, just plug in the usb and if it does, then just change the voltage regulator that is next to the arduino 12v input. Even so what caused this burning isby Fabiano Müller - RAMPS Electronics