WASHINGTON — A new online search tool allows consumers to type in a vehicle identification number, or VIN, to check on whether recall repairs have been completed on a specific car, truck or motorcycle.

The service, which began last week, is available on the National Highway Traffic Safety Administration's website, http://www.safercar.gov.

Automakers must have to provide at least 15 years of data for the tool and update their information every seven days.

The program comes as manufacturers are recalling millions more vehicles than at any other time in U.S. history, about 46 million vehicles so far this year. That's almost 1 of every 5 cars in the U.S. and eclipses the annual recall record of 30.8 million vehicles set in 2004.

The free search tool lets consumers quickly learn whether a vehicle they are considering for purchase has a safety problem that has not been addressed.

Recalled vehicles can be repaired without charge at franchised dealers.

People who want to check first need to get the vehicle's 17-digit VIN.

It can be found where the windshield meets the dashboard in the left corner, on the driver's door post and on insurance and registration documents.

This is the first time consumers will be able to use a VIN on the safety agency's site to determine whether a recall issue has been addressed on a particular car.

The service is also available on NHTSA's Safercar app for iOS and Android devices.

Often, a recall defect isn't addressed by a vehicle's owner even if that person knows of the problem, David J. Friedman, the deputy administrator of NHTSA, said during a news teleconference last week.

"These vehicles can sometimes be sold or rented to someone who is completely unaware of that recall,” he said. “In many cases that can put an owner's life at risk, and risk the safety of others on America's roads.”

Friedman said that when a vehicle was recalled, its owner should have the appropriate repair performed as soon as possible.

Before today, consumers who visited the safety agency's website to check on recalls could search only by vehicle make and model year to learn whether a particular model was, in general, subject to a recall.

They could not, however, find out whether a specific used car — perhaps one they were considering for purchase — had been recalled, but not repaired.

Although some automakers had a feature that allowed consumers to check for incomplete recalls by using a VIN, that feature was not always easy to find if it even existed.

But NHTSA issued a final rule a year ago that required all major automakers and motorcycle manufacturers to provide a VIN look-up tool, to place it prominently on their consumer ver's side.

In the past, automakers' VIN look-up practices varied widely.

Some, like Chrysler, required consumers to register and set up an account on their websites before being able to see recall information with a VIN. That practice created an extra step.

General Motors also once required consumers to register their vehicles with the company before searching for recall information, though it dropped that requirement in 2012.

Finding recall information using a VIN on the Volkswagen website once required typing “VIN lookup” into the site's search bar. Subaru was among the automakers that did not have the feature on its site, but added it within the last month.

The new rule is expected not only to benefit used-car shoppers, but to help increase recall completion rates for all vehicles. The safety agency said only about 70 percent of recall repairs are made.

Recall data will go back at least 15 years under the new rules. Automakers are not required by federal law to perform free recall repairs on vehicles more than 10 years old, but they usually opt to make the repairs anyway.

Regarding privacy concerns, the agency said it would not gather personal information on the site, so it would not be possible to track who has checked the recall status.

This is what consumers can expect when searching for recall information about a vehicle on the agency's website: If there is an open recall, they can see what the manufacturer said in the recall notice, including descriptions of the defect, the safety risk associated with the problem and a description of the remedy.

If a recall repair has not been completed for that particular vehicle, “Recall INCOMPLETE” will appear on the screen in red letters.

If there are no open recalls, consumers will see “Number of Open Recalls: 0” on the page.

If parts are not yet available to fix the safety defect, the warning will say, in red, “Recall INCOMPLETE. Remedy not yet available.”

Consumers who want to check on more than one vehicle never have to leave the page.

After they enter one VIN, they will be told by the program that it is possible to enter another one.

NHTSA said the same information would be available on automakers' consumer websites.

There is no standard location for the VIN prompt on the various sites, but several automakers have said that recall information would be at the bottom of their web pages.

On Ford's site, for example, “Safety Recalls” are listed under the Ownership heading.

On Toyota's site, “Safety Recalls & Service Campaigns” appears at the bottom of the page under the Tools heading.

On Nissan's website, “RECALL INFORMATION” is in a box outlined in white at the bottom of the page to the far right.