Electrical & Lighting

BuildingWrench repair guide

Electrical & Lighting

LED Tube Still Doesn’t Work After Replacement: What to Check

When a replacement LED tube stays dark, the issue may be wrong lamp type, incompatible ballast, ballast-bypass wiring, failed sockets, or no fixture power. Identify the retrofit method before swapping more lamps.

Last reviewed 2026-09-12 · General facility-maintenance information, not a substitute for site procedures, manufacturer instructions, codes, or qualified professional judgment.

Safe first checksSkill: Beginner-friendlyFormat: Diagnose → Fix → Test
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Safety boundary

This guide stops before energized wiring or panel work. Use qualified electrical personnel for internal diagnosis.

Full troubleshooting steps are in Pro

The safety boundary, quick answer and stop-work conditions above stay free. Pro opens the likely causes, symptom table, step-by-step procedure and preventive maintenance for this guide.

Stop and call a licensed professional when

  • Retrofit wiring is unknown
  • Sockets are burned or damaged
  • Internal voltage testing is needed
  • Emergency fixture is involved

Mistakes, FAQ, parts and tools

Pro opens the rest of this guide: common mistakes, field FAQ, the parts list, and the tools for the job.

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Commercial LED Light Flickering: What to Check Before Calling an Electrician

Commercial LED flicker can come from a failing driver, loose lamp, incompatible dimming/control, unstable power, a failing retrofit tube, or occupancy controls. The most useful first step is defining whether the issue follows one lamp, one fixture, one control zone, or a whole circuit.

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Emergency Light Battery Won’t Hold a Charge? What to Check

If an emergency light fails its required test duration, first verify that normal power and charging are present. An aged battery is common, but charger faults, lamp problems, or loss of normal-power sensing can produce similar symptoms.

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Commercial Light Switch Not Working: Safe First Checks

A wall switch that appears dead may actually be part of an occupancy-control system, lighting contactor, BAS schedule, dimming system, or tripped circuit. Map what is affected before touching wiring.

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Breaker Keeps Tripping? What Facility Maintenance Can Check Safely

A breaker that repeatedly trips is signaling a real problem such as overload, short circuit, ground fault, or failing equipment. Identify what lost power, remove obvious loads, and do not keep resetting a breaker that trips again.