The National Highway Traffic Safety Administration is looking into hundreds of complaints from drivers that say the glass in their sunroofs shattered for no apparent reason.
According to one expert, spontaneous shattering can happen if there is a manufacturing defect.
"You should not have to ride in risk worrying about whether your sunroof is going to explode over you," said Clarence Ditlow, The Center for Auto Safety.
Most sunroofs are made of tempered glass which breaks into small, rounded pieces. Some are calling for them to be made of laminated glass like that used in windshields to better protect drivers.