i've using multiwii few days and everything works perfect in my quadrocopter but....
today when i tried to start motors, one of them (connected to D11 ) didnt respond. I thought it may be my ESC or Motor problem but i changed conections with another Motor pin and surprice... another motor connected to D11 doesnt work. I cant find the issue and i need help

Please tell me what i should do.
I've checked connection D11 data witch atmega pin and i'ts ok, gns and + pins are also connected so i really dont know what it is...