How to Solve Light Fixture and Switch Wiring Problems
Andy in New York asks: How do I fix a problem with a light I am trying to install? Wiring Connections for Light Fixtures and Switches.
Wiring Light Fixtures and Switches
- I have a problem with a light I am trying to install in my kitchen.
- The light was originally a fluorescent light but I replaced it with a regular 2 bulb ceiling mount light fixture.
- There are two cables in the ceiling, (black, white and ground wires in each) one is connected to the kitchen light switch and the second cable is coming from an outlet with a motion sensor outdoor light that is always switched on. Both were originally connected to the fluorescent light.
- I cannot get the light fixture, or the outside light working. I tried wiring all blacks (4 wires) all whites (4 wires) and all grounds (3 wires) together-(3 bundles) I have also tried the two black from the light wired to one black and the two white from the light to the other black with the two external white wires together and all three grounds together-(4 bundles).
- It seems like this is a complicated lighting schematic where both light fixtures are getting power from the same source and they need to be wired in parallel.
Not sure what to try next, any help would be greatly appreciated!
This electrical wiring question came from: Andy, a Student from Nesconset, New York.
Thanks for your electrical wiring question Andi.
How to Wire Light Switches and Occupancy Sensors
Application: Troubleshooting and Testing Light Switch Wiring.
Skill Level: Intermediate to Advanced.
Tools Required: Basic Electricians Pouch Hand Tools and a Voltage Tester.
Estimated Time: Depends on personal level experience, ability to work with hand tools and electrical troubleshooting skills.
Precaution: Identify the circuit, turn it OFF and then Tag it with a Note before performing any wiring or inspections.
Wiring Connections for Light Fixtures and Switches
- Identify the Power Source for the Light Fixture
- Using my voltage tester, I would carefully identify the power source, making sure that I test the hot to ground and the same hot to neutral.
- This is done one cable at a time, and one wire at a time.
- Once the power source is identified I would identify the power source cable with black electrical tape, and cap off the wires using orange or yellow wire nuts.
- Wiring Light Switches
- Next, the wiring to the switches will need to be identified starting by looking at the wiring on the switch so I can see which wires are actually connected to the switch.
- Then using the ohms scale on my meter or my continuity tester I would test each remaining cable to identify the cable that goes to each switch.
- I will notice that there are fewer cables left and where they are going is beginning to make since.
- Wiring a Switch for Two or More Light Fixtures
- Because the power source is shared with the two light fixtures, then I understand that the white neutral wire of the power source cable will be connected to the neutral wires of each light fixture.
- Wiring from a Shared Power Source
- The black wire of the power source will connect to one of the wires leading to the light switch, and the return wire from the light switch will connect to the kitchen light fixture.
- Because the outside motion light is hot all the time, then it will connect to the black wire of the power source cable.
- Bonding the Ground Wire
- All of the earth ground wires are connected together using a wire connector.
- Additional ground wires are added to this group of ground wires to provide bonding all of the components of the circuit as follows:
- Light fixtures
- Light switches
- Junction box
- NOTE: Bond the earth ground to these components using Green Grounding Screws and or Bare Copper Wire or Green insulated wire.
More about Wiring Light Fixtures and Light Switches
Light Switch Wiring
Wiring a Light Switch – Diagram 1
Fully explained pictures and wiring diagrams about wiring light switches describing the most common switches starting with photo diagram 1.
Home Lighting Articles
Home Lighting Articles covering recessed lighting, under cabinet lighting, lighting terminology and more.
How to Install Kitchen Electrical Wiring
Kitchen Electrical Wiring
Fully Explained Photos and Wiring Diagrams for Kitchen Electrical Wiring with Code Requirements for most new or remodel projects.