Sub cherche_val()
Dim j, i, val As Variant
With Sheets("Feuil1")
For j = 1 To .Range("A297").End(xlUp).Row
val = Cells(j, 1).Value
With Sheets("Mapping")
For i = 1 To .Range("B65536").End(xlUp).Row
If LCase(.Cells(i, 2).Value) = LCase(val) Then
.Rows(i).Interior.Color = vbRed
End If
Next i
End With
Next j
End With
End Sub