If you have turned the power key switch and the Galvo head is not making any sound, the problem might be with any of the following:

• 15V Galvo head power supply
• Power key switch
• Galvo head

Use the steps below to find out which is causing the problem.

1. Remove the panel on the control unit.
2. Measure the input and output of the 15V power supply (as shown).

• If the reading is normal and the indicator light on the 15V power supply is not lit, replace this faulty power supply.
• If you are not getting a reading from the power input of the 15V power supply, then replace the power key switch.
• If the input and output of the 15V power supply are normal and the Galvo lens is still not energized.

1. Remove the theta lens from the Galvo head.
2. Stick your index finger into the housing of the Galvo head.
3. Feel whether the internal lenses are locked tight in place.

• If they feel loose, replace the Galvo head with a new, identical one. 
• If they feel tight, the Galvo head is normal.