Parmak Precision Mark 5 is a 110‑120 V AC‑operated low‑impedance electric fence charger designed for single or multi‑wire high‑tensile fences, featuring an internal digital performance meter and up to 8 000 V holding power. Common failure points in this class of units include degraded rectifier diodes, burnt‑out MOSFETs, blown capacitors on the DC output stage, and corrosion or loose connections at the fence terminals or grounding strap. First‑check diagnostics: verify that the AC input is within spec and that the unit powers up (LED status indicators), inspect all visible components for burn marks or swollen electrolytics, and confirm that the digital meter displays a valid voltage; if any of these fail, proceed to test the output with a multimeter and replace suspect components accordingly.[oss-gpt-20b]