Which wires in my bathroom light fixture should I connect to live, neutral, and ground?
Asked by Sam Anderson 
2 months ago
Last Updated: October 1, 2024
I’m currently attempting to switch out a busted bathroom light. There are red, black, and brown wires, with black and brown having 4 wires all together. Do you happen to know which one is live, neutral, and ground?
Make sure the circuit is properly grounded when installing a plastic fixture, or call in the professionals
Pointed out that there is a ground present in that box.
Is not equipped to handle the fault current properly.
Seems like the brown wire is actually the neutral wire (it was originally white but discolored over time) and 1 would serve as your switch leg (providing power to the light fixture). The grounds are twisted together on the right side of the picture near the NM clamp, so you’ll need a wire nut for that connection. The bundle of black wires with the crimp cap contains all the hot wires that supply power to outlets and switches.
This appears to be a single wire switch leg. The brown wires, which used to be white and served as neutrals at one point, may also be overloaded neutrals.
Et a meter to accurately measure electrical values.
Make sure to grab a voltage meter and adjust it to 220 volts on the ground setting. Then set the meter to beep in order to check for consistency.
Very old wiring. The color you’re referring to as brown used to be white. White is the neutral wire. Use a red wire nut to connect the white wire from the light fixture to them. Leave the black wires as they are. Connect the black wire from your light fixture to the red one. Remember, this is an old ungrounded circuit. So, do not connect the bare wire from the fixture to anything.
Thank you, !
It seems like there’s a ground wire at the top left under the slotted screw of the box. It’s crucial to bond the fixture properly since this is a grounded box.
Make sure to switch off the breaker first, it seems like a switch loop connected to the wall switch. Keep the wires that are tied together as is. Use Buchanan crimps or tape to cap them. Reuse the two wires from the old light fixture. It’s simple. Best of luck!
Make sure to double check the wires before starting any work. The red wire is probably the switch leg, the black wire is hot, the brown wire is neutral, and the ground wire is located in the back of the junction. Use a meter to confirm.
Ive them a try, you’ll see.
You really need to have a volt meter.
I believe the wires you’re identifying as browned were originally white neutral wires.
All the black wires are hot wires carrying electricity, and the lone pigtail should be used as the switch leg for the light. Therefore, your new fixture needs to connect to the red pigtail and all the ‘brown’ wires you identify as neutrals should be connected as neutral wires from the light fixture.
I can’t help but think… what if they created a device that could indicate the voltage of each wire?
There’s no need for rudeness. I was just trying to find out if such a device exists without going to the store. Now I realize how useful it would be to have one. 🙂
Sir, has come up with a million-dollar idea.
Before flipping the switch, make sure to use a voltage meter to check if the bare wire, which I assume is grounded, could potentially cause an issue with the setup in my house.
Joining switch legs is a challenge thanks to our predecessors
The ‘brown wires’ you mentioned are actually neutral (white) wires. Connect the white wire from the light fixture to the white wires in the ceiling box, and connect the black wire from the light fixture to the red wire in the ceiling box. Do not connect any part of the fixture to the black wires in the ceiling box in this scenario, as the red wire is for the switch.