If you have a sunroof like my 2011, it most likely is leakinf from the drain tube thar runsfrom the top down the passenger side od the rear roof pillar and dow to the rear quarter panel where it drains out t. My tubing was cracked and really hard to get to, so It would fill the jack compartment amd then overflow to the spare. I drilled a small hole in the bottom of the compartment to allow it to drain out.