What to do with extraneous wiring in bathroom fixtures?

August 13, 2022 12:22 PM

I am swapping out old bathroom vanity lights that have an attached 3-prong grounded electrical outlet, but the new fixtures do not have the outlet. I have questions about what to do with extraneous wiring.

The old light fixtures have 3-prong electrical outlets attached to the units (see linked photos). The new units do not have them. I ass-u-me that I just need to cut the white and black wires from the outlet and combine them with the corresponding white and black wires that I will use to wire the new lights. But I'd rather not do so without consulting others with more electrical experience as I am fond of the house and my wife is fond of me.

I'd appreciate answers from electricians or at least people with DIY electrical experience. I have my own guesses obviously. Thank you!

Photos:
1. Old fixture showing on-board 3-prong outlet from the outside.
2. View of wiring inside the old fixture.
3. Close-up view of wiring inside the old fixture.

Obviously I will use the green ground wire as intended with new fixture.

posted by terrapin to Home & Garden (4 answers total)

Best answer: No, you don't need to cut any wires. Instead, you want to unfold the wires in the junction box in the wall, and unscrew the wire nuts. This will disconnect the wires from the fixture from the wires in the wall. Then attach the wires from the new fixture to the old wires in the wall. The bare copper wire is the ground wire.

Some cautions:

• Turn off the power before you do any of this. Also, get a voltage tester to confirm that you've shut off (all of) the correct circuit(s). It's possible (though doesn't look likely) that you could have the outlet on a different circuit than the light.
• Take note of what's connected to what in the existing wiring:
  • It looks likely that both black wires from the fixture are connected together, but if not, you could have one wire that's always on to power the outlet and one that is switched for the light. If so, you'll want to cap the wire that used to be connected to the outlet, and use the one that went to the light to connect to your new fixture.
  • It looks like there's an extra neutral (white) wire there beyond what is needed just to power this fixture, so it's possible that you have another device downstream of this outlet, or that you have a switch leg to the switch. Paying attention to what's there existing (and understanding (or at least documenting) it before you rip it out) can save a lot of head scratching when you go to put it back together.

posted by yuwtze at 12:44 PM on August 13, 2022 [4 favorites]

Whatever you do, take clear photos of the wires in situ and of all steps in case you need to call someone in to work on it later.
posted by nouvelle-personne at 12:49 PM on August 13, 2022 [2 favorites]

Response by poster: Instead, you want to unfold the wires in the junction box in the wall, and unscrew the wire nuts

D'oh. I did notice that pigtail, but didn't process it. Thanks.
posted by terrapin at 1:09 PM on August 13, 2022 [1 favorite]

To be clear turn off the power doesn't mean the light switch it means the breakers for that room and or the whole house. Resetting the stove clock and being off wifi for a few minutes is better than being dead forever. I'd strongly advise you to not diy this if you don't have a basic comfort with how electrical wiring works and don't posses a multi meter and skills to operate.

Re the ground, double check. The new fixture should have a ground lug on its chassis somewhere if it's a permanent fixture you're attaching... It might just look like a little nut on a stud. Sometimes it has the ground symbol on a little sticker but not always.
posted by chasles at 6:55 AM on August 14, 2022