I recently came across this YouTube video through an online forum. It is a clip from a TV news program in New Zealand called Fair Go and follows a story where the interior of a Jeep Grand Cherokee appears to catch fire. Now let me clarify something right away, there is no problem with the Jeep Grand Cherokee, no recall coming, no need to worry if you own one. In fact, the problem can affect EVERY vehicle on the road today.
What happened is the owner of the Jeep placed a water bottle in the rear seat cup holder. The water in the clear bottle acts like a magnifying glass, focusing the sunlight into an intense spot on the interior seating surface. Within 20-30 seconds, the seat surface begins to smoke.
The danger here is real for Jeep owners like myself, and anyone that drives a car. If there had been more flammable items left on the seat (say a newspaper or a book) the owner of the Jeep could have a charred mess for an SUV, rather than just minor seat damage. Fortunately that wasn't the case here.
This is not only an issue in the Jeep Grand Cherokee, as this can happen with any type of cupholder where sunlight can pass through a clear bottle of water and focus on a nearby surface. So the next time you place a clear bottle of water in your vehicles cupholder, take a minute to see if you might have something to worry about.