| Alignment Error / fiber image off-center | Dust or debris in the V-groove or on the fiber, contaminated clamp, or camera/illumination drift preventing proper centering. | V-groove and clamp deep clean, illumination re-balance, camera focus and offset re-alignment, test splicing to confirm sub-0.02 dB results. |
| Fiber not found (left / right): "can't detect fiber" | Fiber set too far across the V-groove, failed LED brightness, dirty objective lens or mirror, or a camera/optical-block fault. | Optical-path inspection, lens and mirror cleaning, LED brightness calibration, camera/sensor diagnostics to the board, optical-block replacement if needed. |
| Arc / discharge problem: unstable arc, sizzling, sparking, bubbles | Worn or contaminated electrodes (typically due around 1,000–5,000 arcs), incorrect arc power, or a high-voltage/arc-board fault. | Electrode replacement and conditioning, arc-power recalibration, high-voltage board check, fresh arc-calibration until GOOD on single-mode fiber. |
| High splice loss / high estimated loss | Drifted arc calibration, worn electrodes, contaminated V-groove, high cleave angle from cleaver, or alignment-motor wear. | Full alignment recalibration, electrode service, cleaver inspection with cleave-angle measurement, motor re-zeroing, verified test splicing. |
| Motor error: Z, X, Y or focus motor fault | Debris or dried lubricant in the motor track, worn drive gears, lost home position, or a motor-driver board fault. | Motor track cleaning and re-lubrication, home-position recalibration, gear/belt replacement, driver-board repair or replacement. |
| Splicer won't power on / no boot / boot loop | Failed battery or charging circuit, faulty DC jack or power board, corrupted firmware, or failed main board. | Power-rail diagnosis, battery and charge-circuit service, DC-jack/power-board repair, firmware re-flash, main-board component-level repair. |
| Screen / LCD blank, cracked, or unresponsive touch | Damaged LCD or touch digitizer, loose display ribbon cable, or a display-driver fault. | LCD and touch-panel replacement, ribbon-cable reseating, display-driver testing, full functional check. |
| Heater / oven won't heat or over-heats sleeves | Failed heater element, broken heater wiring, or a heater-control board fault. | Heater element and wiring service, recalibration of shrink temperature and time, control-board repair. |
| "Too thin" / "too fat" splice geometry | Arc power too high or too low, insufficient or excessive fiber overlap, or stripping length out of spec, usually from calibration drift. | Arc-power and overlap recalibration, motor push/overlap re-zeroing, confirmed across SM, MM and your actual fiber types. |
| PM splicer rotational / axis error (FSM-40PM, 45PM, 100P, FSU-PM) | Polarization-maintaining alignment drift, rotational stage wear, or stress-rod profile mis-detection. | PM-axis rotational re-alignment, stress-rod profile recalibration, rotational-stage service, verified PM extinction-ratio test splicing. |