OTIS MRL FAULT CODES

Hi
I have a fault on this unit which is showing up on the tool as ESB NR.
I'm not familiar with this code and id appreciate it if someone could shed some light on it for me.

Well Pie,
ESB normally refers to Emergency Stop Button. Check those switches starting in the controller for safety chain stop switch. Look around on your control mother board and locate the LED for “C”. If not lit, it’s a stop switch somewhere. That’s about all the light I got for your question.