CAR TALK: Modern odometers may make it easier to turn back time

Dear Car Talk: I understand that most modern cars have electronic speedometers and odometers, and that the odometer mileage is stored in some sort of flash (non-volatile) memory, so it’s not lost if the car loses power.

Do you know what steps the car makers take, if any, to prevent alteration of the memory by unscrupulous sellers? — Ben

Dear Ben: Nice try. Innocent question, I’m sure! Actually, I can tell you that the chip that stores the mileage is inside the car’s computer, making it hard for the average jamoke to tamper with.

But as with most things in this age of computers, professional crooks with the tools and the know-how can tap into the car’s computer and change the mileage.

In a way, it’s even easier than the old days, in the ‘50s and ‘60s, when you could put your dad’s car on jack stands and run it in reverse for two days so he’d never know you drove to the Grand Canyon and back while he was on a business trip.

So, what prevents unscrupulous people from altering a car’s odometer before selling it? Hopefully, the fear of getting caught. It’s a federal crime, subject to significant fines and up to three years in jail. In fact, even as an individual seller, if you replace your instrument cluster or know your odometer doesn’t reflect the real mileage, you have to disclose that on the title when you sell the car or you’re in violation of the law.

But we know laws don’t stop everybody. So, the only sure way to avoid being the victim of odometer fraud is to be a smart buyer. How can you tell if an odometer has been tampered with? Start with a little research.

First, get a vehicle history report, like a Car Fax. That provides you with the historical record of the car’s odometer readings each time the car was sold. If you see that it was sold six months ago and had higher mileage than it does now, you’ll want to report the seller to your state’s attorney general’s office. Similarly, if the car was last sold 10 years ago and has only 2,000 miles on it since then, you’ll want to ask more questions.

You can also ask for maintenance records. Not only does that indicate that the owner was conscientious, but the current mileage is always recorded on the repair order. So that’s another way to verify that the whole story makes sense.

Even without a vehicle history report or repair orders, there are hints that a vehicle’s odometer may have been tampered with. Parts of the car that get touched a lot -- the steering wheel, the driver’s seat, the window switches, the brake pedal -- all show significant wear and tear over the years. If an odometer shows 49,000 miles and the brake pedal is worn flat or the driver’s seat is threadbare, those are red flags.

So you have to do your homework and use common sense. If historical information is unavailable or if there are any red flags, walk away. There are plenty of used fish in the ocean, Ben.

Have a question about cars? Write to Ray in care of King Features, 628 Virginia Drive, Orlando, FL 32803, or email by visiting the Car Talk website at www.cartalk.com.

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