After a updating of the firmware and a small crash four of the eight engines do not work. I’m not sure if it the crash or it the updating that is the failure. What are you thinking? I have tried to upgrade again but nothing happen.
@Gustav89,
Please provide a dataflash log to help troubleshoot your issue.
Wiki http://copter.ardupilot.com/wiki/common-downloading-and-analyzing-data-logs-in-mission-planner/
Regards,
TCIII GM
I have solved the problem. I had upgraded with X4 software instead of X8. 