Private Sub Worksheet_Change(ByVal Target As Range)
marques = Array("AUDI", "CITROEN", "RENAULT", "PEUGEOT", "VOLKSWAGEN")
ab = Array("AUD", "CIT", "REN", "PEU", "VOL")
If Target.Column = 2 Then
For n = LBound(marques) To UBound(marques)
If InStr(UCase(Target), marques(n)) <> 0 Then
Target.Offset(0, -1) = ab(n)
Exit For
End If
Next n
End If
End Sub