Weird issue with ABL Z probe : S

[Drone]

Is there a Gcode command to cut power from the servo?

Check to make sure you don't have this line commented out in your configraton.h in the Bed Auto Leveling section.
#define PROBE_SERVO_DEACTIVATION_DELAY 300

This will cut power to the servo 300ms after either an extend or retract of the servo. It seems it's normal for the servo to get a bit jittery from some circuit feedback in the Arduino if it's left powered on and if you're marginal on 5v power at the Arduino it can cause a too low power condition and print stop or a reboot of the Arduino. This will fix that. You can set the ms delay to whatever you want, but most seem to set that to 300ms and it works well.

I also have had problems with the servo drawing more power than the Arduino 5v can supply and occasionally the Arduino reset during a servo move. So now I leave the Arduino USB connected either to my laptop or my Raspberry Pi and that gives enough extra 5v power that it's no longer an issue.

Not sure if this helps you, but worth a quick check.