ALARM 22

Feedback System Malfunction

Backup battery for the absolute position data detection circuit has dropped voltage — absolute position data may be lost and re-homing required.

Controls: T-32, Fusion 640T, Matrix
Machine series: Quick Turn, Integrex, Slant Turn

Causes

Backup battery for the absolute position data detection circuit has dropped voltage — absolute position data may be lost and re-homing required.
- NardisAmpsforum
  This alarm implies decreases in the voltage of the backup battery for the absolute position data detection circuit of the control card.
Servo system fault — a downstream drive is in alarm 43 (the feedback alarm shows on the NC as alarm 22). Swapping suspect drive with a matching-model spare proves whether the drive or the encoder is faulty.
- cncpiotrforum
  In my case. Was torn wire in the encoder
PLG (encoder) on the spindle has failed.
- mazmanforum
  Please check PLG spindle, possibility PLG spindle spoiled

How to clear it

1
Replace the backup battery, then re-home all axes (absolute position has been lost).
- quoting the Integrex manual entry for Alarm 22forum
  Re-homing is required since the absolute position data may have been lost. Replace the battery.
2
If the suspect drive flashes alarm 43, swap it with a matching-model drive (same MDS- part number) — keep wiring identical but swap the blue rotary switch settings between drives. If alarm follows the drive, it is the drive; if not, suspect encoder/cable.
- onthebumperforum
  If there is another amplifier/drive with the same model number (MDS-...) try to swap it. Make all the connections the same but make sure you swap the rotary switch settings between the drives.

Confidence: high · Three independent forum sources (one PM, two CNCZone) corroborate the battery-vs-servo-drive split. The 'replace battery + re-home' procedure is referenced directly from the official Mazak manual entry as quoted in the PM thread.

First sourced: 5/21/2026