How to interpret the B901 or D9210c Access control interface module LED Status.

LED	Action	State
Heartbeat, blue	LED blinks at 1/2 sec rate.	System is operational.
	LED is solid on or off.	System is powered off or is not operational.
Reader, yellow	LED is blinking rapidly.	LED is off. Card data is executing.
	LED is off.	No card data is being received.