Subaru Problems? Ask a Mechanic for Answers ASAP
Hello and welcome to Just answer.com, Super mechanic here. About your vehicle.
You will want to check for power to the actuator when the button is pressed. Or you can check the actuator by running power and ground to it from the battery, (hint, you can also use a 9 volt battery just to see if it will activate) being that it is so far from the battery. Here is what the data base has for testing it.
Trunk Lid Lock Assembly INSPECTION