The Polatech SMD Reader Head Assembly is a precision optical or magnetic sensor module used in industrial linear encoders and cutter monitoring systems to detect position increments. Common failure points include misalignment of the read‑head relative to the track, contamination on the sensor surface, degraded photodiodes or magnetoresistive elements, and power supply ripple damaging the integrated circuitry. Begin troubleshooting by verifying that the supply voltage matches the specified ±5 V (or 12 V) range and checking for proper ground continuity; inspect the head assembly visually for dust, scratches, or mechanical damage, and use an oscilloscope to confirm clean signal waveforms from the output pins before proceeding to component replacement.[oss-gpt-20b]