During the winter, water can freeze around the door's weather strip, locking you out of your car. If you pull hard to break the ice, the weather strip can tear right off the door. Here's how to fix the weather strip and prevent it from tearing again.
Buy a tube of weather-strip adhesive, a can of nonflammable spray brake cleaner and a can of spray silicone (all are available at any auto parts store). Then pull the weather strip away from the door and clean it and the metal surface with the brake cleaner. Let that dry completely, then squeeze a bead of the adhesive onto the weather strip and the door and let that dry. Then apply a second coat to both surfaces and press the weather strip into place. Clean up any adhesive messes with the brake cleaner.
Hold it in place with masking tape until the adhesive dries (about 45 minutes). Then pull the tape free and spray silicone on the weather strip on the other doors and trunk lid. That will prevent ice from sticking to them. It's good preventive maintenance to treat all the weather stripping before winter every year.