3: A failed cambox position cable or sensor may cause the machine to think the arm is at the home position. The Z Axis comes down and bends the arm. Refer to Cambox Proximity Sensors section in this document.
Minor burrs or gouges on the double arm can visually be removed with a small file without needing replacement.
Go to parts.haascnc.com to find the correct double arm for your machine. Follow the replacement instructions that ship with the assembly.
If the double arm is not bent check the double arm alingment. Refer to Side Mount (SMTC) - VMC - Double Arm - Alignment for instructions on how to check the alignment.