A Consumer Reports investigation reveals a scary occurrence with no known cause.
Have you ever wondered whether those glass sunroofs and panoramic roofs that are now so popular in new cars could, perhaps, explode? Like literally shatter into countless pieces of sharp glass scattered all over you, your passengers, and the entire interior. You can stop wondering because this is actually a thing, according to a Consumer Reports study that also cites the National Highway Traffic and Safety Administration. It's more common than you think and automakers aren't doing much about it, at least not yet.
CR cites NHTSA data showing 859 cases of exploding sunroofs that were reported since 1995. That doesn't sound like much, but the problem actually got worse over time. An alarming 71 percent increase of exploding sunroof was reported since 2011, and industry experts still don't have enough information in order to figure out why this is happening. There is one theory, however. Because the size of the glass sunroof has increased (panoramic sunroofs, for example), too much heat may be getting trapped, preventing the glass from expanding as it should. CR's own investigation found that not only are automakers not taking this seriously, but that they're not even acknowledging it to begin with.
Another disturbing point is that "safety standards and regulatory oversight of sunroofs have not kept pace with those dramatic size and design changes and that more needs to be done to guarantee they are safe." Experts currently don't agree on the exact cause of shattering sunroofs, but they all concur on this: "The bigger the expanse of glass, the harder to ensure that it won't shatter." Which automakers topped CR's list for most exploding sunroof complaints? That would be Hyundai followed by Ford, with 119 and 85 cases, respectively, since 1995. Nissan was third on the list with 82 reported cases. However, it was the Scion tC with the highest number (71) of reported incidents during that time period.
The tC and the entire Scion brand has been discontinued, but that's not the point; there are still a lot of Scion tCs still on the road. Following the tC on the list is the Hyundai Veloster at 54. One Veloster owner whose sunroof suddenly shattered for no apparent reason described the experience like this: "A shower of glass fell on me. I managed to get to work with a bloody arm and forehead, and thank God I had no other cars close to me when it happened." Ford, for example, denied the warranty claim from the owner of an F-150 whose sunroof exploded. The guy had to have it repaired under his own insurance. But the bottom line here is that automakers need to start investigating what's going on.