You will notice that this error code is not in the SAMrf user manual, but is is commonly seen.
Typically, it has to do with the small switch/nub inside the keyhole getting stuck in. It is supposed to retract in when a key is presented but if it gets stuck, it can cause the lock to power-cycle continuously until the batteries die.
Using a small tool, such as a flathead screwdriver, can help you feel for it to see if it is stuck up. You can compare with a properly working lock for reference.
Attached is a picture of where to find the switch/nub on the upper, inner wall of the keyhole of the lock.
Contact your distributor if you are having this problem.