Sub Remplace()
Dim i As Long, ARemplacer As String
ARemplacer = "Renault" ' adapter le mot à remplacer
With Worksheets("Feuil1") ' adapter le nom de la feuille
For i = 2 To .Range("B" & Rows.Count).End(xlUp).Row
.Cells(i, 2) = Replace(.Cells(i, 2), ARemplacer, .Cells(i, 1))
.Cells(i, 3) = Replace(.Cells(i, 3), ARemplacer, .Cells(i, 1))
Next
End With
End Sub