The Mystery of the Flickering Porch Lights

After installing the patio door (see this post) I got to add a couple porch lights to this East Nashville home. Adding wiring in an older home like this has a tendency to be a nightmare at times, because the wires are inaccessible and the walls are plaster. I didn't run into these problems on this project, but I did have a mystery to unravel at the end.

THE SETTING

The homeowner wanted me to add a couple wall mounted porch lights to add more light to his porch. He had showed me a light switch at the front door that he wanted me to use because it didn't seem to do anything.

After a little research I figured that there must have been a ceiling fan in the front room at one time, and the switch controlled the fan. This was a great find, because I could use the switch and junction the wires in the attic without running any new wires to the switch.

I ran new wires from the attic down to the location of the new wall-mounted porch lights. Thankfully, there weren't any studs in my way and this process went smoothly. Whenever mounting exterior lights on clapboard siding I like to first cut out a place to add some kind of mounting board, usually some sort of 1x8. Otherwise, the fixture won't sit flat against the wall and instead lean in or out at an angle.

THE MYSTERY

After running the wires and installing the fixtures it was time to turn on the breaker and give it a try.

Yea! The lights came on and the switch worked.

Wait... the lights went off... one came back on... now they're both on...

What!???

This continued for several minutes. The lights were coming on and off independently of the switch. Sometimes together, sometimes not.

Usually, there's a logical explanation for these types of things. In this case, I retraced my steps in my mind. My first thought was to check the switch. It was the same old switch that had previously not been used. Perhaps it was faulty. I replaced it with a new one.

Same problems.

Hmmm... all the wires from the switch and the attic come together in a junction box in the attic. Perhaps one of the wires is not making a good connection. So, off to the attic I went to check the junction box. I took it apart and put it back together. Let's check it again.

Lights still flickering! Oh my!

At this point, I was starting to feel quite befuddled. I checked the connections at the fixtures. Thinking that a wire might be broken or had a nail in it, I went into the attic and wiggled wires while the homeowner watched below to see if that changed anything. No luck.

At this point, it was time to pull out the box and find the instructions.

I started looking over the first page and read the words "Motion-Activated..."

AAAAAAAAAAHHHHHHHHHHHHH! Mystery solved.

It turns out that the lights were a gift to the homeowner and he didn't realize they were motion-activated. I installed them without looking much at the box or instructions. The sensors were very small and matched the finish of the fixture and the adjustment knobs were hidden at the bottom where I didn't see them.

I was so glad to find the answer to this one. You know the old saying, "If at first you don't succeed, try reading the instructions." I'll take that to heart.

I guess it at least makes for a good story...

:)

-Peter

www.CarpentryGuy.com