I agree with BrianG. I also heard that you can a UBEC or RX pack and it will help the ESC's BEC. I remembered one occasion with my first 7018. It was cogging a lot with 12 NiCd, but I installed the rx pack and it stopped cogging. A few months later the light turned on my head LOL and I took the black jumper out, but it was working fine before with just the rx pack.

I have bad news . I was programing my 9920 & it took but know it wont do anything. I started with a half charged battery & checked all my connections & nothing. I even took out the LVC & still nothing. I guess i have to buy a new ESC

I would fiddle with it a bit more. If it programs, then it should work. Try simplifying the setup as much as possible to eliminate other causes. I would use a 2s or 3s pack and use the internal BEC just to see if the ESC lives, and then go from there.

GOOD news it works. I disconcected the koolflight UBEC & used the stock one & it works on 4s . So does that mean the ubec i just bought went bye bye ?.

UPDATE
It just stopped working again.

I even tried a different reciver & still nothing. Owell i guess it's to buy another ESC.

after more testing it will work with a reciver pack, but not with a ubec or the sbec

Do you have any servos hooked up when you program it? I ask this because if there is an issue with a servo and it is pulling too much current for the UBEC to handle, the UBEC may be causing the receiver to malfunction. A receiver pack has more current capability. If that's not it, try a capacitor on the UBEC output to help eliminate any noise. I assume you disable the built-in BEC when using an external BEC or Rx pack?

yes i pulled the black bec jumper. Yes i have the steering servo hooked up. Maybe i popped the UBEC. I dont have any caps to put on it. If i have to run a reciver pack it's no big deal. Im going to buy a new controller any way.

I ran my converted X1cr last night, & it got real hot & thermaled. My ? is sinice there are no moving parts on it, what is everyone's opinion on removing the heatshrink to help it get some air to help cool it ?. Also i noticed when it gets hot just before thermal when brake is applied it goes in to reverse even thou the reverse is disabled.