Motor Emergency Stop

After I upgraded the FC to 4.0.2, the motor emergency stop does not work properly. I can trigger it by a switch but cannot resume it to ‘OFF’ unless I unplug the battery. It worked in 3.6.x without problem. Thanks.

Got a telemetry log?

Copter 3.6.x, there was CHx_OPT, it’s changed to RCx_OPTION in copter 4.0.x. I also notice that in Mission Planner-> Config/Tuning->Extended Tuning, RC7 Opt, RC8 Opt, etc no parameters are shown after FC upgraded to 4.0.2

Good day, which version of MP are you using ?
I’ve done some test with my tatanis x9d evo plus…i dont have found any issue about the motor interlock on ch7.
Just give us few info in more pls…so we can check

There is a change of dead zone from 3.6 to 4. You now need your switch channel to go lower than 1200 to switch off and higher than 1800 to trigger. You might need to re-calibrate your transmitter, or change the mixer slightly.

MP 1.3.70. You can check Mission Planner-> Config/Tuning->Extended Tuning, RC7 Opt, RC8 Opt, etc to see if there is any value. Thanks.

Just perform the radio calibration… check the switch you have set for it… after you perform the calibration just set the channel on rc7… rc8… etc.
Just set on the radio the correct value for make it work.
Very important… just test the behavior without props
Which radio are you using?

I am using Jumper T16. Before I upgraded to copter 4.0.x, all worked fine.

just adjust the value on the radio settings