‘Sadly dealerships do this all the time’: Car expert reveals the one tip that can save you from buying a used car with major issues

Soaring interest rates on financed cars have pushed many people to consider a used car. But buying from a private seller or used car dealership can be risky. Undisclosed accidents or defects can turn a bargain into a costly repair.

But one car expert shares a handy tool you can use to check the condition of a used car before you buy it, without taking it for an inspection.

In a TikTok with over 124,000 views, Royalty Auto Service (@royaltyautoservice), a mechanic, shows how to use a diagnostic tool that plugs into the dashboard. Once plugged in, information about the car's condition can be displayed on your phone.

The mechanic explains that used car sellers frequently "clear the codes" by resetting monitors, which check for engine, airbag, seatbelt, air conditioner, catalyst condition, and more. By resetting the codes, you may unknowingly drive a car off the lot that has a serious issue, only for a warning light to come on miles down the road.

But clearing the codes doesn't hide defects completely.

A diagnostic tool will tell you if codes have been cleared, showing them as "incomplete."

Which monitor should you check when buying a used car?

While you should check all monitors displayed on the diagnostic tool, the TikToker says there's one that is most important to check.

"The big one that you're looking for is this catalyst monitor," the mechanic says. This monitor tracks the condition of the catalytic converters, a component near the engine that controls fuel efficiency and emissions.

"This [monitor] takes weeks to run," he says. So, if you buy a used car with its codes cleared, you may only notice the issue well after purchasing the vehicle.

According to AutoZone, replacing a catalytic converter can cost upwards of $2,000.

The mechanic says to look out for words like "pending," "history," or "incomplete." It's also a red flag if the diagnostic tool says all vehicle codes have been cleared, showing "no codes found."

"If any of these codes say incomplete, you know it's been cleared, and the car hasn't been driven long enough to run all those monitors," he says. "You don't want to buy it until all the monitors are done."

Buyers respond

In the comments, prospective used car buyers react to the mechanic's tip.

"Been diagnosing cars for over ten years and people... this is GREAT advice. Dad's the best, y'all," a viewer says.

"This is a very good video….. I’m a car guy, and this is very true," another writes.

"I love that you guys are so transparent," a third adds.

Others say they have tried to use a diagnostic tool when buying a car—to varying degrees of success.

"I had a dealership tell me I couldn't hook a scan tool to a car I was interested in. I walked out," one writes.

"Whenever I look at a vehicle I'm interested in buying, I always take my scan tool with me. I've looked at some that the light was out because the bulb was missing and had a list of codes," another says.

@royaltyautoservice Protect yourself!! #tips #automotive #viral #cartok #buyingacar #dealership #fyp #foryou #mechaniclife #mechanic #duet #stitch @gearwrenchtools ♬ Pop beat BGM / long version(1283324) - nightbird_bgm

The Daily Dot reached out to Royalty Auto Service via contact form and TikTok direct message.

Internet culture is chaotic—but we’ll break it down for you in one daily email. Sign up for the Daily Dot’s web_crawlr newsletter here. You’ll get the best (and worst) of the internet straight into your inbox.

Sign up to receive the Daily Dot’s Internet Insider newsletter for urgent news from the frontline of online.

The post ‘Sadly dealerships do this all the time’: Car expert reveals the one tip that can save you from buying a used car with major issues appeared first on The Daily Dot.