Trunk keeps opening by itself

To separate a random mechanical release issue from an electrical issue, ensure the trunk is locked by pulling the trunk open in its locked state. Shake the trunk lid up and down with hands pressing down then trying to pull it open. If the trunk is secure, next step is testing your remote's trunk release button. If worn, a light press on the button may send a trunk release signal. The button should have resistance to pressing like the Lock and Unlock button. If your remote is original, a worn trunk release button may be inadvertently pressed, sending a trunk release signal to the body control module commanding the trunk solenoid to open the trunk. If your remote developed a sensitive trunk button, you can try opening it, remove the battery, rubber membrane and circuit board for cleaning. Cotton swabs and rubbing alcohol can help clean and remove dirt buildup. Let dry, reassemble and test all buttons.