Press the master door lock switch in as shown to lock or unlock all doors.
Using the Master Door Lock Switch
When you lock/unlock either of the front doors using the master lock switch, all the other doors lock/ unlock at the same time.
Honda Civic Service Manual. Trunk Lid Lock Cylinder Removal and Installation (2-door DX models except KC
models)
823110
Removal
1.
Trunk Lid Lock Cylinder
1.
Disconnect the cylinder rod (A).
2.
Remove the bolts (B).
...