Troubleshooting by symptom

These faults are typically optical or focal rather than a failing source. Check the following before adjusting power.

• A contaminated or loosely seated protective window
• Focal distance off by a few millimetres, often after a lens or fixture change
• Power below the marking threshold for the alloy or coating
• Contamination on the fiber connector face

The source is emitting, but energy is not reaching the workpiece. Verify the following in order.

• An open interlock or shutter that the software reports as ready
• The beam obstructed or clipped upstream of the scan head
• The source in standby while the galvanometers execute the job
• A material that does not absorb at the source wavelength

Bowed lines or squares that do not close indicate a correction data issue rather than a hardware fault.

• An incorrect field correction file for the installed lens
• A lens change without recalibration of the working field
• A loose mirror or scan head mount
• Thermal drift that appears only after extended runs

Connection failures are usually a version mismatch in the control chain rather than a failed board.

• A control board or dongle not enumerating on the selected port
• Driver version that does not match the installed software
• Board firmware older than the software requires
• A USB cable exceeding the reliable length for the interface

MOPA color marking operates within a narrow process window. Any variation in inputs will shift the result.

• Pulse width and frequency not fixed to a documented pair
• Inconsistent surface preparation between parts
• Part temperature rising over the course of a run
• Hatch overlap high enough to re-mark the previous pass

The pointer is a positioning aid, not a reference. Alignment should be corrected at the beam path, not the pointer.

• Pointer alignment adjusted in place of the beam path
• A lens changed without re-checking the pointer offset
• A protective window seated incorrectly in its holder
• A pointer diode displaced during shipping