Circuit description
WARNING: This page is about a different car, the 2018 Subaru BRZ. However, it is still accessible from the selected car via links, so may be relevant.
If the entry trunk compartment lock-in prevention function does not work, communication between the indoor electrical key antenna ASSY no. 3 (trunk interior antenna) and the electrical key transmitter SUB-ASSY might be faulty, interference from external radio waves might be present, or the collation ECM (smart key ECM ASSY) might be faulty.