Because of how BTT has their endstop filtering done on their boards it can make the EZABL not function correctly when connected to the Z endstop. You should use the “Z-Probe” port instead of the “Z-STOP” port for connecting to the EZABL signal side. If you are using our firmware then make the connection to the Z-Probe port and enable the EZABL_ON_SERVO_HEADER option in the firmware.
