j'ai trouvé, merci
Option Explicit
Private Sub Worksheet_SelectionChange(ByVal Target As Range)
Range("G9, G12, H15, G18, G21, G24, I24, G27").Interior.ColorIndex = 16
If Not Application.Intersect(Range("G9, G12, H15, G18, G21, G24, I24, G27"), Target) Is Nothing Then
ActiveCell.Interior.ColorIndex = 6
End If
End Sub