A colleague tells the story of his wife backing into a pole with her new SUV. He was incredulous because the SUV had a backup camera.
She explained, “but it didn’t beep!” Therein lies the difference between a backup camera and a backup sensor, and why it’s important to know about each.
Put simply, backup cameras show you what’s behind your vehicle, usually as an image on your car radio screen. But if you don’t bother to look at the screen, they can’t help you. Backup sensors are the opposite. They don’t provide an image but they give you a warning “beep” that gets faster as you near an object.
A camera is more effective than a sensor, especially for detecting a moving child rather than a solid object behind the car, according to the US Dept. of Transportation. The image of a child or object behind the car elicits a better reaction time from the driver. Sensors can also miss objects or false alert, causing you to ignore a real alert, it said.
Ideally, you want both a camera and sensor, says safety advocacy group kidsandcars.
So here’s a few details on each.
Backup cameras–The US government believes that backup cameras are so critical to safety, it ruled they be included in all cars produced from June 2018 and on.
If your car lacks a backup camera you can buy one from a car stereo retailer or Best Buy, Aftermarket cameras typically mount on a license plate holder or bumper. Then you need a screen to send the image to, ideally the car car radio screen.
If your radio isn’t compliant, you can swap it for a new one (typically starting at $250 plus installation although there are very inexpensive radios out there for as low as $100 with stripped down features).
Stay away from the cheapest cameras (under $79). They may deliver a grainy image that’s hard to see. The step up models ($100 to $150) offer better visibility at night or in foul weather.
Another option is to actually replace your rear view mirror with a “smart mirror” that has a built in LCD screen. When not in use, it looks just like a typical mirror, but when the car goes into reverse, an LCD screen appears with an image showing what’s behind the car. Mirror prices vary but a ballpark estimate is around $500.
Backup sensors– The sensors mount on the back bumper of the car and work by emitting ultrasonic waves that bounce off of objects behind the car. The closer you get to an object the faster the return waves are bouncing off the car (hence the faster beeps).
Sensors come in 2- or 4-unit systems. If you have a larger bumper you may need four. And if there’s an obstruction in the bumper like a cross bar, you may only be able to fit two. Either way, expect to pay for about 1 to 2 hours of installation labor plus the cost of a sensor kit, which starts at $99 but can run to about $500 depending on the vehicle and the quality of the installation.
Lastly, some companies make sensors with a video output so you get a color coded readout on your car screen indicating how close you are to an object.
Photo: kidsandcars.org showing 62 children that cannot be seen by the driver of the SUV.