Outlet Reading

On my tester all three lights lit up with no explanation on the tester. Can someone help with this kind of readout. what could be wrong with the outlet? Ground and neutrals reversed, etc.


This usually indicates a 240 volt circuit.

You can also get this with a bad connection, either in the wiring or a loose connection to one prong of the tester. The tip off is 2 of the lights will be about half brightness.

All three lights where nice and bright. This outlet is in a kitchen, above the counter.

I noticed it is by a counter, It should be a GFCI. All 3 lit up, might not be grounded. Is it an older house with with 2 wires, hot and neutral that someone has put in a 3 prong rec? And maybe grounded it to the box which would be a false ground.

You could confirm this with your SureTest, but as I said, it usually indicates an improperly wired, 240 volt circuit (if all lights were bright and equal).

A bad or false ground will not give this indication. . .

Do you own a voltage non-contact ticker?

if you do…ticker both slots and if it is 240V both sides will activate the ticker…to rule out 240V or not.

If this is the only receptacle that caused this…then 1.) You call it out because something appears wrong, and 2.) if it reads 240V with the ticker then you know it is not a plug thats allows 240V to it…

greg is right however in that usually if something is wrong in the unit it will have (2) lights not nearly as bright as one of them…in the end call it out IF you tester does fine on all other plugs other than this one…needs to be looked at to be sure…either way that is not a plug designed for 240V so if that was the case…it needs to be addressed.

Did you ask the owner/seller if there was anything funny with that receptacle? Have them plug in one of THEIR appliances and prove it to you.
If the blender or mixer sounds normal it is not 240v. :wink:

Probably not SOP huh?

Ok all

Just put a volt meter on it.

Radio shack under $20.00

Does anyone have a problem with this??


Paul, the volt tick will not prove 240. A receptacle on a circuit that has an open neutral upstream and a load downstream will show line voltage on both slots.

Are the neutral wires double tapped in the main panel?

Where are you going with this?

As you can see by the attached schematic.

Three-prong tester schematic.jpg

Keep it to HI basics…not diagnosis as they are not electricians so on a counter top that tests out all ok except a single receptacle on a counter…and no others would not lead a person to that diagnosis…they can use the ticker to verify it just is not right and report as such…

It will prove something is wrong…and if none other on the counter does it ahead and beyond i would stick with report it versus diagnostic theories…now if other read the same i would then agree…but since it is isolated on a counter circuit i would think others would exist… either way it is report worthy…as a loose neutral ahead could cause it BUT all factors need to apply.

I still think this is a question you ask the seller. Let him plug in a blender (table lamp or something) to prove there isn’t a problem. I bet the worst case is he has to jiggle the plug to make it work.

Typically the cheaper Radio Shack testers do not have the safety protection that model that costs a little more would have. The safety aspect is certainly worth the extra cost.