The electric trunk latch solenoid can get stuck in the open position making it so the trunk will not latch closed. The diagnosing technician should verify correct electrical connection at the solenoid and check for correct cable routing. The trunk latch most commonly will need to be replaced.
Car Problem Reports
Mercury Milan Trunk Will Not Latch Closed
Mercury Milan Problem
Average Mileage: 63,000 mi (32,000 mi - 95,000 mi)