When an outlet seems to have power, for example a tester lights up, but nothing you plug in works, it is often because the outlet has a loose or failed connection that shows voltage with no load but cannot actually deliver current, or there is a partial fault, a wiring problem, or an issue with what you are plugging in. An outlet that tests as having power yet runs nothing is a confusing but telling symptom. Understanding the likely causes helps you know what to check and when to call a professional.

Here is why an outlet can have power but nothing works.

Voltage without the ability to deliver current

A common explanation is that the outlet shows voltage but cannot deliver real current under load. A loose or deteriorated connection can let a tester or voltage detector read voltage, because almost no current flows for that, while failing as soon as a real device tries to draw power. So the outlet looks live but collapses under load. This points to a bad connection at or feeding the outlet, which is both the cause and a potential hazard, since loose connections arc and overheat.

Check the simple things first

Before assuming a wiring fault, rule out simple causes:

• Test with a device you know works, in case the original device is the problem
• Check whether the outlet is switch-controlled, as some outlets are turned on and off by a wall switch
• Check for a tripped GFCI that protects the outlet, and press reset
• Try another outlet to confirm the device works elsewhere.

These quick checks can explain many cases where an outlet seems powered but nothing runs.

A partial or high-resistance fault

If the simple checks don’t explain it, the outlet may have a partial or high-resistance fault. A connection that is loose, corroded, or partially failed can provide just enough contact to register voltage but not enough to carry a working load, or can cause the outlet to work intermittently and weakly. This kind of fault is a wiring problem that needs a licensed electrician, and it is a safety concern because of the heat a poor connection generates.

It could be the device

It is also worth confirming the issue is the outlet and not what you are plugging in. A failed device, a bad cord, or a device that needs a reset can make it look like the outlet is at fault when the outlet is fine. Testing a known-good device in the outlet, and the suspect device in a known-good outlet, quickly tells you which side the problem is on. If the outlet runs a known-good device, the outlet is likely fine.

When to call an electrician

If a known-good device won’t work in the outlet, no GFCI or switch explains it, and simple checks come up empty, the outlet likely has a wiring fault that needs a licensed electrician. A connection that shows voltage but fails under load is a classic sign of a loose or failed connection, which is a hazard as well as an inconvenience. Rather than keep using or poking at it, have an electrician diagnose and repair it.

An outlet can have power but run nothing when a loose or failed connection shows voltage with no load yet cannot deliver current, or when a partial fault, a switch, a tripped GFCI, or the device itself is involved. Check simple causes first, a known-good device, a controlling switch, a tripped GFCI, but if a good device still won’t work and nothing simple explains it, the outlet likely has a wiring fault that needs a licensed electrician, since it can also be a safety hazard.

Stella Electric diagnoses and repairs faulty outlets and connections for homeowners across the Baltimore area and throughout Maryland, with flat-rate pricing and no overtime charges. If an outlet has power but nothing works, we can find out why. Financing is available on qualifying projects.