If it is a cantilevered area as in this case place your hand at the base of the wall and feel for.
Superhydrophobic wall siding leaking water.
Ultimately water began to appear on the floor of the kitchen inside.
Then using a drywall saw cut along the line you just scored.
Use a utility knife to score a line about 10 inches 25 cm long into your drywall at the location where you see visible signs of a water leak mold discolored drywall etc.
My photo above of ice below some courses of vinyl siding traces a moisture problem traced to improper installation of a through wall vent for a direct vent heating appliance.
Water leaks at soffit or eave overhang penetrations for chimneys that permits water to leak at the roof surface then pass behind the siding if the chimney is not properly flashed.
The wood clapboard sided home shown above located in poughkeepsie new york was badly damaged by leaks into the wall that ensued from yankee gutter leaks and downspout leaks below a roof valley.
Although vinyl is impervious to water when installed as directed by the manufacturer vinyl siding as a whole is not completely watertight.
Wood siding leaks damage.