9920 cooked, used BEC without the jumper on?

[Nick]

I run a 9920 & 7XL.

Recently I jumped up from 14cells to 16, then again from 16 to 18. It ran amazing. 18 is the way forward, the speed the power and it even ran cool with a fan on top! I loved it.

I use a reciever pack and the servo ALWAYS was powered by this reciever pack but yesterday, I plugged everything in. It moved 2 foot then stopped. I disconnected everything then reconnected everything one at a time. I noticed that the reciever pack wasn't doing anything if it was unconnected the servo was working from the ESC! I tried connecting the reciever pack in again then tried to turn but it only faintly moved, then suddenly all the wires from the reciever pack/ESC melted and smoke gushed out from the 9920.

The 9920 looks dead and smells it to.

What I just can't understand is how this happend. I thought the 9920 only used the internal BEC if both jumpers were on?

*Confused* Hope someone can clarify this. :002: