I have a Tsugami NT 12 with a Fanuc 3T control.

The machine goes into Spindle Indexing alarm (machine alarm, no alarm code shows up on the Fanuc screen), 8 of 10 times when I use the M-codes for spindle orientation.I suspect perhaps the encoder is not working properly. Since I have 2 similar machines where the other is working perfectly, I figured to try and test the encoder from the other machine. Now my questions are what is the procedure for this? How do I "reset" or "zero-return" the encoder afterwards? I do not have a controlled axis, so there is no actual procedure for zero-ing the spindle.

Please, any help is much appreciated.