1. If the red dot guider is gone but the laser fires,

• check if the "red dot" parameter is set to 4.  For LightBurn users, enable "blanking".
• If the red dot is still not showing up, replace the laser source.

2. If the red dot guider is gone and the laser does not fire either.

• Remove the cover of the control box.
• Measure the voltage of the line. The normal reading is 24V/48V.

• If the voltage reads normal, replace the laser source.
• If the voltage reads abnormal, replace the laser power supply.