On most units the protection light going dark is the explicit end-of-life signal — the unit still powers devices but no longer clamps surges.
Stop and call a licensed electrician or emergency services now if there's smoke, sparks, a burning smell, heat, shock, or water near the problem. Otherwise it's safe to answer the questions below.
The likely readout
Most likely cause
Protection is spent or degraded — the unit keeps delivering power but is no longer clamping surges
Ranked by fit to your answers
1
Protection is spent or degraded — the unit keeps delivering power but is no longer clamping surges
90
SAFE NEXT CHECKTreat it as an unprotected power strip and replace it; it will keep delivering power but is no longer clamping surges. Choose a replacement with a status indicator.
Where to stop. Swapping a plug-in surge strip is homeowner-safe. If the "Grounded" light is off, the receptacle itself may be ungrounded or miswired — confirm with a plug-in tester, and because correcting house wiring means live conductors, if a tester shows an open ground have a licensed electrician verify the outlet. This is general information, not a quote and not a substitute for a licensed electrician.
Try the safe next check above. If it doesn't resolve it, or would mean working on wiring or a panel, stop and call a licensed electrician — don't replace parts on a guess. Open the full tool to change any answer for your exact situation, or try a related check below.
source-governed · verified 2026-06-20
Sources
standard UL 1449 — Standard for Surge Protective Devices · verified 2026-06-20
Electrical Fault Check provides general diagnostic information only. It is not professional advice, not a quote, and not a substitute for a licensed electrician. Do not work on live wiring. If you see smoke, sparks, burning smell, heat, shock, water exposure, or repeated tripping, stop using the circuit and contact a licensed electrician or emergency services as appropriate.