The issue many have faced with the RC of the Mavic saying MECH ERR has upset a few new owners of the Mavic Pro. But rest assured people, this issue is being worked on. There will be a general release firmware available soon to eliminate the possibility of this issue happening.
If yuo are experiencing the issue, you can email DJI Support ( email@example.com ) asking to be placed on the “test” list of users who can immediately download the update. I expect the firmware to make GR very soon.