How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Mike G. Your Own Question
Mike G.
Mike G., Master Electrician
Category: Electrical
Satisfied Customers: 6971
Experience:  Proven Professional 46 years Experience
Type Your Electrical Question Here...
Mike G. is online now
A new question is answered every 9 seconds

I have a strange problem I need help with. I have a wall outlet

This answer was rated:

I have a strange problem I need help with. I have a wall outlet that tests an open negative. The strange thing is the outlet is wired on the lower end of the outlet with correct wiring. The top portion of the same receptacle has no wiring attached and reads the open neutral. The outlets to either side of the improper outlet are wired correctly and the garage is powered from a 90 amp circuit from the main panel fed with 2 30 amp fuses. The garage is divided into 2 circuits. Any advice you could provide would be greatly appreciated.
Hi, I'm Mike and I'll be glad to assist you. There must be an outlet or junction ahead of the problem. A quick way to know is to short the circuit hot to ground. This will kill the circuit and you will then see what is ahead of the problem.
Customer: replied 2 years ago.

how do I short the hot to the ground?? Black wire to grounding screw??

Try this procedure first.

Wiggle Procedure

You have a circuit with dead outlets and maybe some dead lights on it or you’re experiencing flickering on a circuit. You will need a 2 wire voltage tester to check the outlet. A Multimeter or a Volt/Con are suggested. I prefer the Volt/Con because there are no settings to make, it does continuity and is audible. Success begins with knowing what you’re looking for.

1] No voltage reading between the hot and the neutral or ground indicates an open hot.

2] No reading between the hot and the neutral but 120V between the hot and ground and 120V between the neutral and ground indicates an open neutral.

3] No continuity between the neutral and ground – Check for tripped GFCI device first

4] If all the branch circuit breaker are on you have a bad connection on the hot or neutral wires. The usual cause is a bad connection, either a termination on a device or connection in a wire nut.

Over the years I’ve found the easiest way to locate the opening needing examination and correction is to wiggle the devices.

5] The first step in this exercise is to get a lamp to act as an alert. Make sure the lamp works and in the on position. You may also use something like a vacuum cleaner or blow dryer, for an audible alert. Don’t use anything electronic, like a radio.

6] Plug it into a dead outlet.

7] Now with a cube tester or any plug you will need to go to all the dead outlets and any live outlets in the area, insert the plug and wiggle the device side to side slightly. Watch the test lamp or listen for the other alerts as you wiggle the devices.

If the loose or bad connection is present the wiggle action may make it contact briefly and the lamp or the other things will alert you . Having found the suspected outlet all that is left is to correct the bad connection.

If the device is a push back wired device, this probably is the cause of the circuit failure. All wires must be terminated under the screws. Also you should never put more than one wire under a screw.

This troubleshooting procedure works in most cases and won’t have you open boxes un-necessarily. Keep in mind that the problem is in one of two places in the circuit, either in the first dead outlet or the live outlet just ahead of it.

Customer: replied 2 years ago.

thanks so much I did try the wiggle method as you described and nothing on the light "flickered" even detached the receptacle from junction box and tried again with no disruption and still open neutral. The receptacle directly in front has adequate wiring with correct indicator lights on hand held tester. Can there be 2 grounding wires attached to the grounding screw on one outlet. I did disconnect the two grounding wires and reattached with one only and still open neutral. I am obviously not an electrician but this one is frustrating

There being 2 ground would say that one is supply side and the other is to the down strean outlets.
Customer: replied 2 years ago.

sorry to keep bothering you LOL. The two ground wires were created from running an additional outlet above the original outlet. Only one portion of the original outlet was wired so I ran a new wire from the top portion of the original outlet to a new outlet above the original. When the open neutral occurred I completely detached the new outlet wiring and still have open neutral. Frustrating as can be

No bother. If the procedure didn't work only means that the neutral wire isn't close enough to make contact with a wiggle or it is open in a light fixture opening or junction box. Either flash the circuit as I originally told you or install a tempory jumper between the neutral and ground. This would make the outlet live and when the circuit is turned off at the breaker you will see if other outlet go dead and thus show where you need to examine for the open.
Customer: replied 2 years ago.

Will that be a stripped wire from ground to neutral and I don't have a breaker its on a 30 amp fuse

That is no doubt why you lost the neutral. The circuit being over fused cause the wire or connections to fail with an overload. The jumper from the ground to the neutral only re-establishes the circuit for testing.
Customer: replied 2 years ago.

should the fuse be replaced with a smaller amperage and what you are saying is the circuit is full and can not handle another outlet

Circuit should be fused for the wire that was used. #14 wire = 15A, #12 wire=20A. The outlets are also rated for the circuit and 30A is way over.
Customer: replied 2 years ago.

wow ok will check the wire size and replace with proper sized fuse will that restore the neutral and allow proper function. Thanks for all your help I appreciate your time and patience with me on this

You're welcome. In todays world breakers are the way to go. You might consider a panel change to avoid future problems.
Customer: replied 2 years ago.

I know I have an old Wadsworth panel and the garage is a square D fuse panel and the cost to replace these will be significant. If I replace the fuse with proper amperage will that restore safe operation.

Yes it would. They make a breaker fuse that would be better instead of a standard fuse.. That would be a better alternative.
Mike G. and other Electrical Specialists are ready to help you
Customer: replied 2 years ago.

Thank you again for all your help you have been excellent

Well, thanks and good luck.

Related Electrical Questions