WRONG,

Battery Failsafe is a program in the receiver that will drive the throttle to the idle position if the receiver battery voltage drops to near a dangerously low level. It has nothing to do with the programable failsafe.

If the Rx battery is low or too low capacity, the flight loads on the servos will drag the voltage down, then the engine goes to idle. Also a maneuver that loads up a servo will set it off. Moving the throttle stick to idle will reset it to normal operation.