Option Explicit
Sub Rouge_jaune()
Dim c As Range
Application.ScreenUpdating = 0
Sheets("Tableau1").Range("i:k").Interior.ColorIndex = xlNone
For Each c In Sheets("Tableau_2").Range("i2:k10000").SpecialCells(xlCellTypeConstants)
Select Case c
Case "Z": Sheets("Tableau1").Range(c.Address).Interior.ColorIndex = 3
Case Else: Sheets("Tableau1").Range(c.Address).Interior.ColorIndex = 6
End Select
Next
Application.ScreenUpdating = -1
End Sub