Auto Tech

How General Motors' reverse lights make a fool of you

Why are they on when the car isn't in reverse?

CNET
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I got an email from viewer Mackenzie in Jacksonville, Florida, asking me about something I had never noticed before: late model GM cars with reverse lights on when they aren't in reverse.

We picked up a 2017 Chevrolet Impala to check it out and the reverse lights do -- or at least can -- come on when you use the remote locking function from the keyfob, unrelated to the car backing up. 

It's meant to light the area around the car at night and can be set to stay on for as long as 2 minutes. But other drivers prowling the parking lot, waiting for your space, may be inspired to blow a gasket thinking that you're taking your damned sweet time backing out of your spot. The fact that most cars have darkened windows these days doesn't help figure out what's going on.

The federal vehicle lighting regulations seem to have no problem with this feature, specifying that reverse lights:

  • Must be steady burning
  • Must be activated when the ignition switch is energized and the car is in reverse
  • May never be activated when the vehicle is in forward motion

So nothing GM is doing flouts regulations, as you might have guessed about a carmaker with an army of lawyers. There are also regulations on lamp brightness, as well as the fact that nothing says a car must have two reverse lights. It just looks better to most designers' eyes.

Next time you're waiting forever for a GM car to back out of a space, check if you can even see someone behind the wheel.