Water leaking into the trunk caused a short which left my trunk light on all the time, resulting in many rescues, and making sure to carry jumper cables, as well as eventually a dead battery. The short was fixed, a new battery purchased. But there is still some water getting into the trunk. Not enough to swim, but enough to store items in waterproof bottom containers. This occurs whether the car has been driven or not, so it isn't from underneath. A Honda forum member had written to say he had problems with water getting into the trunk around the rear lights. He said he fixed it by applying a waterproof sealer around the exterior of the lights.