I went through this a couple of weeks ago. F23 and F24 kept blowing when turning my turn signals on, which caused my brake lights and turn signals to go out. The dealership replaced the multifunction switch, which fixed it for approximately 3 minutes. On my second trip in (couldn't drive the car all 4th of July weekend because of no brake lights or turn signals
), 6 shop hours later they were able to find the short that was causing the fuses to blow (and therefore, concluded that this short also caused the MFS to fry as well). Right where the driver-side rear seat folds down there is a cluster of wires running to the back, and over time the folding of the seats had worn the insulation off of the wires, causing the short. You may want to check there and see if those wires are worn down. If they are, fix them up, replace the fuses, and see if that helps. If not, you may want to look at the MFS.
