Ford Mystique Owner's Manual page 78

Trunk
To open the trunk manually, use the oval key.
Remote Trunk Release (If equipped)
The remote trunk release is on the floor to the left of the
driver's seat.
The remote trunk release
You can disable the remote trunk release. If you depress the
lever on the trunk latch that is marked in orange before closing
the trunk, the trunk can only be opened with the key.
Disabling the remote trunk release
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