You might try something like


For Each oneShape in Sheets("Summary).Shapes
    If oneShape.Caption = ws.Name Then
        If oneShape.Type = msoFormControl Then
            If oneShape.FormControlType = xlCheckBox Then
                ClearContent = True
                Exit For
            End If
        End If
    End If
Next oneShape

If ClearContent Then
    With ws.Range("H:H")
        For i = 1 to .Cells(Rows.Count, 1).End(xlUp).Row
            With .Cells(i, 1)
                If LCase(.Text) = "y" Then .ClearContents
            End With
        Next i
    End With
End If