detached garage no power
#1
Member
Thread Starter
Join Date: Feb 2014
Posts: 11
Received 0 Votes
on
0 Posts
detached garage no power
Hello everyone, i am a new homeowner and i want to be a handy homeowner and not have to call in a guy for everything small.
I am having trouble with my garage, it has all the wiring hooked up, but there is no power going to any thing in the garage.
I checked the breaker and it is not tripped, i used a tester and the breaker shows it has power and is live.
When i go to the garage, the outside gfi outlet has no power, inside outlet has no power, switches/light fixture does not turn on, and the connected flood light doesnt turn on.
I tested the wiring splitting area and it shows no power. What are the steps i need to do to trouble shoot this?
Should i change the breaker first? Check the wire splitting box? (the wire is a yellow 20amp wire that goes underground into the main house)
Here is picture of how it is currently wired (please forgive me, i am not sure how to properly draw electrical diagrams.)
Thank you
I am having trouble with my garage, it has all the wiring hooked up, but there is no power going to any thing in the garage.
I checked the breaker and it is not tripped, i used a tester and the breaker shows it has power and is live.
When i go to the garage, the outside gfi outlet has no power, inside outlet has no power, switches/light fixture does not turn on, and the connected flood light doesnt turn on.
I tested the wiring splitting area and it shows no power. What are the steps i need to do to trouble shoot this?
Should i change the breaker first? Check the wire splitting box? (the wire is a yellow 20amp wire that goes underground into the main house)
Here is picture of how it is currently wired (please forgive me, i am not sure how to properly draw electrical diagrams.)
Thank you

#2
Welcome to the forums.
Where is the wire split box ?
You checked the wire at the breaker and it's ok. How does it get from the panel to the wire split box ?
You mention yellow wiring which sounds disturbingly like NM-B (romex) cable which is not designed for underground burial.
Where is the wire split box ?
You checked the wire at the breaker and it's ok. How does it get from the panel to the wire split box ?
You mention yellow wiring which sounds disturbingly like NM-B (romex) cable which is not designed for underground burial.
#3
Member
Thread Starter
Join Date: Feb 2014
Posts: 11
Received 0 Votes
on
0 Posts
I think the wire goes from circuit breaker along the inside wall then goes under a concrete slab and under the lawn then pops out from the garage floor. Its in a metal tube when it pops out of the garage floor. I also see where the floor was dug up to place the wire. I can actually follow it until the concrete slab then it goes behind the wall and it shows itself back at the panel.
The wire split box is inside the garage, it is actual the first thing the main line comes up into then splits into various things.
So far everyone told me that 20amp yellow wire will rot and i will have to dig up the ground, etc...
This is the exact layout, yellow being the yellow wire.
The wire split box is inside the garage, it is actual the first thing the main line comes up into then splits into various things.
So far everyone told me that 20amp yellow wire will rot and i will have to dig up the ground, etc...
This is the exact layout, yellow being the yellow wire.

#4
Nice diagram. 
If you check the house end of the yellow cable and it is getting power and you check at the garage end and it's dead..... then that pretty much leaves you a defective piece of non waterproof cable that needs to be replaced.

If you check the house end of the yellow cable and it is getting power and you check at the garage end and it's dead..... then that pretty much leaves you a defective piece of non waterproof cable that needs to be replaced.
#5
It is not a yellow wire. A wire is a single conductor. It is a yellow cable (two or more wires in a metallic or non metallic sheath. Yellow indicates it is NM-b (AKA Romex). NM-b is for dry locations only. Buried conduit of any kind is not a dry location. If the conduit is EMT it is not suitable for burial and has probably rusted through.
Assuming you used a multimeter, or test light but not a non contact tester then the breaker is probably good. Since it sounds like the wrong kind of cable in the wrong kind of conduit you are most likely need to replace the feed to the garage. You can either use UF-b direct burial cable buried at 24 inches or PVC conduit with individual THWN wires buried 18 ". If you go with UF-b no conduit is need except where it enters and leaves the ground. If you use a GFCI breaker you can bury it as shallow as 12".
Two other points though not related to your problem but need to know when you redo it. There must be a disconnect (switch) where power enters the garage before anything else. I don't see one on your diagram. If you use a SPST switch it should be rated 20 amps and of good quality. The second point is all receptacles in the garage must be GFCI protected.
i used a tester and the breaker shows it has power and is live.
Two other points though not related to your problem but need to know when you redo it. There must be a disconnect (switch) where power enters the garage before anything else. I don't see one on your diagram. If you use a SPST switch it should be rated 20 amps and of good quality. The second point is all receptacles in the garage must be GFCI protected.
#6
Member
Thread Starter
Join Date: Feb 2014
Posts: 11
Received 0 Votes
on
0 Posts
ah, i am sorry about using the wrong terminology.
The yellow cable is "supposely" newly put in, the garage had no power, but the previous seller put it in 4 months before i bought the house.
He say the power was working fine.
Now, everyone tells me the yellow wire is no good, because it will rot really fast.
Is it possible to use this wire until it rots somewhere and then dig up the ground and put in a new one? Is it anyway safe to do so? If is it not, i will disconnect the breaker and wire for now and just have no power to the garage until summer time and have someone fix it.
Assuming, its fine and i just need to add a switch in the garage, (it does not have one) Do i take out the breaker or shut it off, buy the switch box, hook it up to the feed coming from the ground then have each outlet or fixture come into the new switch box, (kinda like a mini circuit breaker in the garage?)
Also i used a digital multimeter (5 dollars from harbor freights its a cheap one)
The yellow cable is "supposely" newly put in, the garage had no power, but the previous seller put it in 4 months before i bought the house.
He say the power was working fine.
Now, everyone tells me the yellow wire is no good, because it will rot really fast.
Is it possible to use this wire until it rots somewhere and then dig up the ground and put in a new one? Is it anyway safe to do so? If is it not, i will disconnect the breaker and wire for now and just have no power to the garage until summer time and have someone fix it.
Assuming, its fine and i just need to add a switch in the garage, (it does not have one) Do i take out the breaker or shut it off, buy the switch box, hook it up to the feed coming from the ground then have each outlet or fixture come into the new switch box, (kinda like a mini circuit breaker in the garage?)
Also i used a digital multimeter (5 dollars from harbor freights its a cheap one)
#7
The yellow cable goes directly to your panel. You can see the white, black and ground conductors. You can see where the wire goes in to the circuit breaker. Check for voltage right at that point. Visually make sure the white and ground are connected.
If all is ok at this point and there are no more splices between the panel and the garage you need to go to the garage splice box and check for voltage there between black and white. If you don't have the voltage in the garage..... the cable is defective.
If you have confirmed that the cable is defective then your course of action is clear.... replace the cable.
If all is ok at this point and there are no more splices between the panel and the garage you need to go to the garage splice box and check for voltage there between black and white. If you don't have the voltage in the garage..... the cable is defective.
If you have confirmed that the cable is defective then your course of action is clear.... replace the cable.
#8
While EMT is not iIdeal if they used EMT for the entire run since it is only 4 months old you may be able to pull the NM-b and pull in 3 THWN wires. With breaker off I'd carefully dig a hole a few feet from the garage, then in the middle of the run, and finally a few feet from the house to see if the conduit is contentious.
Note: you need to use a multimeter, solenoid tester, or a neon test light to check the breaker not a non contact tester.
Note: you need to use a multimeter, solenoid tester, or a neon test light to check the breaker not a non contact tester.
#9
Member
Thread Starter
Join Date: Feb 2014
Posts: 11
Received 0 Votes
on
0 Posts
sorry, i dont understand a few of the words, but this is what i think you said.
disconnect the yellow cable, and attached the proper wire to the end of it and pull it out the other end? (the underground part i will say is about 20-25ft and then i can reach both sides inside the garage or the house.
I think the yellow cable is encased in a metal 6" tube, so i can kinda pull it like a string with the new wire attached?
disconnect the yellow cable, and attached the proper wire to the end of it and pull it out the other end? (the underground part i will say is about 20-25ft and then i can reach both sides inside the garage or the house.
I think the yellow cable is encased in a metal 6" tube, so i can kinda pull it like a string with the new wire attached?
#10
disconnect the yellow cable, and attached the proper wire to the end of it and pull it out the other end?
With breaker off I'd carefully dig a hole a few feet from the garage, then in the middle of the run, and finally a few feet from the house to see if the conduit is contentious.
I think the yellow cable is encased in a metal 6" tube
#11
Member
Thread Starter
Join Date: Feb 2014
Posts: 11
Received 0 Votes
on
0 Posts
ah yeah 1/2" not sure why i changed it to 6" i had 1/2" earlier.
i'm just thinking, i'm not at home right now, but would it be possible for him to use romex from circuit panel to a junction box near the the exterior wall of the house, then the proper cable to go underground and then back up and use romex for the fixtures/switches?
Not really sure why, maybe to save cost? I've looked up the cost of romex and the other cables and the cost is significantly different.
Or it would be stupid and he would have made life easier and just pulled one wire from breaker to the garage?
i'm just thinking, i'm not at home right now, but would it be possible for him to use romex from circuit panel to a junction box near the the exterior wall of the house, then the proper cable to go underground and then back up and use romex for the fixtures/switches?
Not really sure why, maybe to save cost? I've looked up the cost of romex and the other cables and the cost is significantly different.
Or it would be stupid and he would have made life easier and just pulled one wire from breaker to the garage?
#12
but would it be possible for him to use romex from circuit panel to a junction box near the the exterior wall of the house, then the proper cable to go underground and then back up and use romex for the fixtures/switches?
The underground wiring should have been UF cable. It's heavier duty and waterproof. It's not much more than standard NM-B (romex) cable.
Just a quick check on going prices......
50' 12-2 NM-B (romex) 26.00
50' 12-2 UF 45.00
#13
Member
Thread Starter
Join Date: Feb 2014
Posts: 11
Received 0 Votes
on
0 Posts
ok, thank you all for your help. i think i got a good grasp on it. I will go around and test everything again and try to trace out the actual wiring.
Just to confirm, the proper wiring should be like this?

green being ground
white being neutral
black being hot
underground is UF
indoors is romex
Just to confirm, the proper wiring should be like this?

green being ground
white being neutral
black being hot
underground is UF
indoors is romex
#14
While not a code violation best practice is not to run cable in conduit. It would be extremely difficult to pull UF-b through ½" conduit. Better to go with one black, one white, one green*, THWN wire.
*If you have EMT (metal conduit) you don't have to have the green ground. The conduit can serve as the ground. However many electricians will pull a green ground just as an extra precaution.
*If you have EMT (metal conduit) you don't have to have the green ground. The conduit can serve as the ground. However many electricians will pull a green ground just as an extra precaution.
#15
*If you have EMT (metal conduit) you don't have to have the green ground. The conduit can serve as the ground. However many electricians will pull a green ground just as an extra precaution.
#16
While correct, the diagram shown above could be simplified. The GFI could be mounted in a 2 gang box with the disconnect switch, That box would also be used to feed out to the other parts of the circuit.
Even when new you it would still not be easy to pull UF in a 1/2" conduit with any bends in it.
Even when new you it would still not be easy to pull UF in a 1/2" conduit with any bends in it.
#17
Member
Thread Starter
Join Date: Feb 2014
Posts: 11
Received 0 Votes
on
0 Posts
so i went to shut off the breaker to the garage to make sure no one gets hurt or just have power feeding into the soil.
Turns out the breaker also shuts off my fridge outlet!
Either i have the wrong breaker, or there is a hidden junction box somewhere behind the wall. There are no visible access or blank cover plate anywhere in the house.
I was going to do all the wiring for the garage and cap it off until i can replace the underground cable/wires.
Now i can not even do it safely because i am not sure i have the right breaker.
There is only 2 new romex going into the panel, one is going upstairs for microwave and one for the garage those are the only 2 places.
Now i think either i have the wrong breaker or he might have used an old white romex and then junction box somewhere near the wall and then extended NEW yellow romex to the garage.
I have no idea where this wire is coming in from or where a junction box is. ( i thought all junction boxes must be accessible...)
also to simplify, i can use one big "2 gang box" as the junction box and include the switch and gfi outlet right?
Turns out the breaker also shuts off my fridge outlet!
Either i have the wrong breaker, or there is a hidden junction box somewhere behind the wall. There are no visible access or blank cover plate anywhere in the house.
I was going to do all the wiring for the garage and cap it off until i can replace the underground cable/wires.
Now i can not even do it safely because i am not sure i have the right breaker.
There is only 2 new romex going into the panel, one is going upstairs for microwave and one for the garage those are the only 2 places.
Now i think either i have the wrong breaker or he might have used an old white romex and then junction box somewhere near the wall and then extended NEW yellow romex to the garage.
I have no idea where this wire is coming in from or where a junction box is. ( i thought all junction boxes must be accessible...)
also to simplify, i can use one big "2 gang box" as the junction box and include the switch and gfi outlet right?
#18
i thought all junction boxes must be accessible...)
Three suggestions for your Easter egg hunt. If you are reasonably certain you have the right breaker and the refrigerator is on the same circuit open the refrigerator receptacle and see if you have two cables.
The other is to look for outside receptacles.
See if you can find where where at the house the garage cable comes out of the conduit and then use a non contact tester to determine when you have the right breaker.
also to simplify, i can use one big "2 gang box" as the junction box and include the switch and gfi outlet right?