Nearly 900 vehicle recalls were filed with the National Highway Traffic Safety Administration in 2015, a new record involving more than 51 million vehicles — another record, the federal agency reported.

"That is slightly above 2014's record, which after adjustments stands at just below 51 million," said NHTSA Administrator Mark Rosekind during a speech at the Washington Auto Show.

In 2014, there were 803 recalls filed. NHTSA initially believed those recalls covered nearly 64 million vehicles. But the agency made corrective adjustments after discovering that many vehicles involved in the Takata air bag recalls had been counted more than once. Also, some Takata recalls have been moved from the 2014 total to the 2015 total.

Just because a vehicle is recalled doesn’t mean it’s quickly fixed. Sometimes the needed volume of replacement parts isn't readily available, as was the case with many of the Takata air bag recalls. And sometimes automakers struggle to locate all current vehicle owners to notify — especially when recalls involve early-model vehicles. Too often, though, a vehicle owner learns of the recall but procrastinates making the dealer appointment for the repair and eventually forgets about the problem. 

Every year an average of 25% of recalled vehicles are left unrepaired, according to NHTSA.

Last week, 18 automakers and the U.S. Department of Transportation reached an agreement to work more closely together to identify manufacturing defects earlier and improve the overall safety recall process.

One of the agreement’s provisions is to develop ways to increase recall participation rates among vehicle owners. To that end, NHTSA, which is part of the Department of Transportation, has launched "Safe Cars Save Lives," a new advertising campaign.

“Safe Cars Save Lives is a critical effort for building public awareness of recalls and is the first national campaign aimed at empowering vehicle owners,” said Rosekind. “Millions of vehicles are recalled every year. Old, new, used or leased — one of those recalled vehicles could be yours.”

NHTSA is urging vehicle owners to get into the habit of checking their vehicle identification numbers (VINs) using NHTSA’s free VIN look up tool.