How do I diagnose lights that won't turn on?

Question

When we purchased our house a year ago, I replaced all the burnt out lights throughout the house. 2 of the recessed lights in our master bath were out but within a couple months of replacing them they went out again. Our light switch does have a dimmer so I chalked this up to not buying bulbs that were dimming compatible and since we didn't really need them i just never replaced them again. A few months ago the other 2 recessed lights started flickering anytime they were turned on and then eventually would turn on for a few seconds and then immediately go out. I tried replacing the bulbs, making sure to get dimming bulbs, and flipping the breaker but neither fixed the issue. Our vanity lights, vent fan and all the outlets work in the bathroom no problem.

What are some next steps I can take to try to find the root cause before calling in an electrician?

Answer 1

There are three likely possibilities:

• Bad connection, either at the switch or at one of the light fixtures
• Bad switch
• All fixtures failed

Assuming the fixtures take standard (i.e., 120V) bulbs, there really isn't much to fail in the fixtures, except for loose connections. So I would start with the switch. Since they only cost a few dollars (some are less than $1, but I would go up a level to get one with either screw-to-clamp or Wago-style connections), just replace the dimmer with a regular switch. If that solves the problem then you can still go ahead and put in a dimmer, but you will know that you have a fall-back solution. If that does not solve the problem then at least you have simplified things a bit while you investigate the next likely problem - the connections to each of the fixtures.