Red Light, Green Light

The Puzzler

RAY: This is from my traffic signal series. Truth be known there was only one puzzler in the series, 'til today that is!

You may recall the other traffic signal puzzler was about these new LED traffic lights that seem to be popping up just about everywhere. And well they should; they're fabulous.

#1. They hardly ever burn out. And because every light consists of dozens of those little diodes, even if some of them do burn out, the light still works, unlike the old incandescent bulbs, which burn out and leave you with no signal whatsoever.

More than that they use a small fraction of the energy of the old incandescent bulbs.

And #3. They're brighter! So win, win, win, right? Wow, this is great! Now, of course, it costs quite a bit to purchase and install these lights, but in the long run they're worth it.

However, as magnificent and wondrous and splendid as these LED lights are, they do have one disturbing shortcoming -- one flaw, one defect, if you will. What could it be?

Now before you go off the deep end, I'm going to give a hint. If I had waited a few more months before using this puzzler some of our listeners might have found it a little too easy.

Think you know? Drop Ray a note!

[ Car Talk Puzzler ]

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