Zareba A25LI is an AC‑powered low‑impedance electric fence charger rated to energize up to 25 miles of wire or tape with a 1‑joule output and digital timing control. Common failure points for this model include loss of power due to tripped circuit breakers or faulty plugs, internal fuse burnout (though the unit is fuseless, external fuses may be used), degraded transformer windings causing reduced voltage, and corrosion or loose connections in the high‑voltage output leads. Initial troubleshooting should verify that the 120 V AC supply is present and stable, inspect the indicator LEDs for normal operation, check all wiring terminals for tightness and signs of wear, and measure the output voltage with a high‑impedance voltmeter to confirm proper energization.[oss-gpt-20b]