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301 B axis communication error on fanuc control

301 B axis communication error came up on a fanuc controlled machine that had scales for the B- axis or rotation of table. After troubleshooting everything and getting down to that it had to be the scale. Ordered a new scale and tried it. Unfortunitly the same alarm occured. After looking into the parameters I was able to tell that someone had turned off the scale at one time because all the paramters had told me so except for one. Parameter 1815 bit 1, bit4, and bit 5 were all 1's. This indicated scales were turned on however every other parameter and there were about 8 of them were indicating a pulse coder setup. After changing 1815.1 to a zero the 301 b axis communication alarm went away. 

The customer must have lost home position and went to reset it and thought that bit 1 was supposed to be a one since two other machines it was when scales were turned on. 301 b axis communication error solved.