Some basement basement lights not turning on, or delayed on.

[tommymc]

Hi, I'm a new DIY member hoping to get some suggestions on a (to me) perplexing problem with my basement overhead lights. There were originally 4 of them, and through the years, I've added 4 more by running cable from the existing fixtures. They are all controlled by three 3-way switches which turn all the lights on at once. I've also run several outlets on the same circuit for the workshop. I've had the same basic setup for 30 yrs. Two days ago, an issue developed where one light came on as usual, then there was a long delay before others started cascading on. By yesterday, this delay had reached several minutes. Last night, it deteriorated further, and only 3 lights come on, no matter how long the wait. All the lights are LED bulbs screwed into ceramic fixtures. I also don't think they are coming up to full brightness. I've tried replacing bulbs, and have an incandescent that works in some fixtures but not others. I've unplugged all my power tools so there's nothing on the circuit other than the overhead lights.

I'm not sure how to troubleshoot this. An open connection or mouse-eaten wire wouldn't seem to explain the delayed on. An explanation for what could delay or dim bulbs that test perfectly well in other fixtures would give me a starting point. This all came on suddenly, with no apparent trigger event. Any suggestions will be greatly appreciated.

Edit/update: According to my understanding of the original circuit, there were 4 ceramic fixtures which I'll order 1,2,3 & 4 in the order I believe they're wired. #1 always comes on, and for testing that's where the incandescent bulb is. #2 (LED) comes on, although it seems dim. When I put a bulb (LED) in #3, it comes on for a second, then goes out and #2 comes on. wtf? #4 doesn't come on at all. I've also disconnected the feed to the workshop lights and receptacles, which all came through #2.

 

[tommymc]

SOLVED! Suspecting low voltage might be causing the strange LED behavior, I put a multimeter on the #2 fixture and measured only 50 volts. Next I opened the only other original fixture (#4) that had newer lights tapped into the box.....and found a burnt mess. The original wires (which had been crimped and taped) were fried.....insulation melted and broken copper. The smoking gun, so to speak. I don't know why the breaker didn't trip, or how any voltage was still going through the circuit. I also don't know what caused the melting in a box that hadn't been touched for close to 30 yrs. After trimming back the wires and replacing the fixture, all seems back to normal. Thanks to anybody who reads this and has any comments.