A dead outlet, how to trace back ?

An outlet in my bathroom is dead, It is GFCI socket. I tried reset at the socket with no luck. There is no tripped breaker at the panel. I removed the entire socket and measure the black wire. This way, I know it is not the GFCI socket itself. There is no power coming in. I have no idea what goes in between the main panel and this broker outlet and I have no idea which breaker controls this outlet. Since there is no power, I cannot isolate by flipping individual breaker. All lights and outlets (those that I am aware of) in the house works.
As suggested in the sticky post, GFCI sockets are one of the things to check. Since this broken one is already a GFCI socket, is it normal to put multiple GFCI on one circuit or normal there is only one for one circuit ? Any suggestion on how to trace back to the main panel so that I know what is broken in between ?

 

The following only applies to single pole breakers.Have a good lamp plugged into an outlet in every room/hallway. Have all lights controlled by a switch on in every room/hallway. .Turn first breaker off and view which lights and lamps are off and make note. Turn first breaker on and second breaker off. View which lights/lamps are off and make note, Repeat for all remaining breakers. This should allow identifying breakers and 90 % of their loads. The remaining 10% of the loads will take a little longer but most likely powered by 1 or 2 of the noted breakers for that area. Mark the breaker panel.

 

What year was the house built?
It was common when GFCI first came out to put one GFCI receptacle for several areas. The common places to find GFCI on one of these circuits is garage, outside, basement, other bathrooms. Look behind the pile of boxes in your garage if you can't find it.

 

They do make wire tracers but they ain't cheap.

You are going to have to check all lights and receptacles close by. If you have a basement it may even be down there or up on a second floor. Usually electricians will take the shortest route possible as they are not fans of pulling wire.

Do you know what a tripped breaker actually looks like in your panel.
On my panel it is obvious but there are panels out there where it is hard to tell if the breaker is tripped.
Not until you push it to off and then back to on is it apparent that it is tripped.

Right now it sounds like you have lost power to only this box so odds are it is a bad connection in a wirenut at another box.

 

The house is about 20 years. It is actually 3 sockets that are dead. I have one bathroom on the main floor and two on 2nd floor. The GFCI socket I mentioned is main floor bathroom. It is connected to the socket in 2nd floor first bathroom and then to the 2nd floor 2nd bathroom. The 2 sockets on 2nd floor bathroom are not GFCI. It looks like that only one GFCI is used to protect the entire circuit. Since there is no power to the first one, the two on the 2nd floor are dead too. I used a volt meter to measure the voltage at the output side of the breakers at the panel. They all have the right voltage. So there is no unnoticed tripped breaker. This is purely speculation. If the last two sockets are just normal sockets, the electrician may have decided to use only one GFCI for the entire circuit, there may not be another hidden one. TO be safe, I looked very carefully through out the entire house. All other GFCI socket that I can find have power. BTW I identify GFCI sockets by the Test/Reset button on the socket. Is there any GFCI socket that have Test/Reset somewhere else which make it looks like a regular socket and caused me to miss them ?

 

Repeat.
What year was the house built?
It was common when GFCI first came out to put one GFCI receptacle for several areas. The common places to find GFCI on one of these circuits is garage, outside, basement, other bathrooms. Look behind the pile of boxes in your garage if you can't find it.

 

You did pull the outlets in the other bathrooms to make sure those are properly connect or not shorted out.

 

I would remove the GFCI outlet in the first floor bathroom and temporarily install a normal outlet. Today's GFCI outlets have a separate connection to serve downstream outlets. The downstream connection on the GFCI may be dead.This will test this theory and if the other outlets become live, then the fix is to replace the first floor outlet with a new GFCI.

 

OK so when you pulled the GFCI you had wires to the socket Line but also wires connected to the Load connections on the GFCI.
Correct?
If there was not any wires connected to the Load GFCI terminals then this GFCI is not controlling the other sockets that are without power.
When you measured the power it was from black to white of the Line connection.
Correct?

You said you checked the breaker so you know what breaker controls them is the breaker marked as to what else it controls?
If yes then that is where I would look for a bad connection.