Hi all. I don't know if you've fixed your alarm yet, but I was having the same alarm after replacing the old Electo-Craft servo in my HRT7 rotary with the newer Magmotor servo. The alarm was caused from the temp sensor in the servo not being connected. The Magmotor servo does not have a temp sensor. So I just shorted the two black wires that used to go to the temp sensor and away went the alarm. You cannot change parameter 24 that sets if the temp sensor is open, or closed without calling Haas to get the password to enable protected parameter write.
Also, if you need to replace the servo in your rotary, keep the encoder from the old servo if it still works. I moved the encoder from the old servo to the new one, and it worked perfectly, no need to change any parameters.
cheers,
Michael
www.cncfusion.com CNC kits for Sieg mills and lathes