Subaru 2004 Impreza Owner's Manual page 131

Keys and doors
! Inspection
Perform the following steps at least twice a year to
check the release handle for correct operation.
1. Open the trunk lid.
This places the latch in the locked position.
2. Use a screwdriver with a thin blade. Slide the
screwdriver blade from the slit aperture of the lock as-
sembly fully to the end until you hear a click.
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