First, make sure you are booting up the laser marker following the right procedures:

• Connect the power cable to your machine and then to a 3-prong socket, which must have a working ground wire. 
• Ground the machine using the ground wire on its back.
• Flip the rocker switch on the back of the machine. The indicator light should light up and stay on. 
• Turn the emergency stop clockwise to release it. You should hear a light, buzzing sound coming from the Galvo head. 
• Turn the power key switch in the right direction. You should hear the fan blowing inside the control unit, indicating the laser source has successfully booted up. 

If you have followed the correct procedures and the machine remains inactive, use the three scenarios below to troubleshoot. 

Scenario 1: The rocker switch on the back of the machine is not lit. 

1. Check whether the wall socket that the machine is connected to has power.
2. Check the fuse in the 3-in-1 switch.
3. If both have been tested normal, replace the 3-in-1 switch on the back of the control unit. 

Scenario 2: The Galvo lens remains silent with the emergency stop released. 

The problem might be with any of the following:

• 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 power supply.

• If the reading is normal and the indicator light on the Galvo power supply is not lit, then replace this faulty power supply.
• If you are not getting a reading from the power input of the power supply, then replace the emergency stop with a new, identical one.
• If the input and output of the Galvo power supply are normal and the laser marker 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.   

Scenario 3: The fan is not running after the power key switch has been turned on. 

1. Remove the panel on the control unit.
2. Measure the input and output of the power supply of the laser source.

• If you are not getting a reading from the power input of the power supply but no reading from the power output, then replace the laser source power source with a new, identical one.
• If the output is normal and the laser marker is still not energized.

1. Check the continuity of the power key switch.
2. If it has tested normal, replace the laser source with a new identical one.