In AUTO mode the copter land

I have my first big problem with Arducopter from 2013.
After the upgrade to 3.5 all was fine, the autotune, all flights mode and auto mission too.
After to have changed some parameters for trigger camera (pwm mode instead of relay), yesterday I go to fly and when I switch to Auto the copter start to land.
I have recall the old parameters list (befor the pwm change) but the problem stay.
All other flight mode are perfect (RTL, LOITER etc…)

Solved today everything’s worked normally.