Yaka faire comme ça :
Sub test()
Dim a, aa%, ab%, i%, ii%
a = Worksheets("Feuil1").Range("TRef")
For i = 1 To UBound(a, 1)
aa = a(i, 1) * 12 - 4
ab = a(i, 1) * 6 + 185
With Worksheets("Feuil3")
Worksheets("Feuil3").Range(.Cells(1, aa), .Cells(1, aa + 10)).EntireColumn.Hidden = (a(i, 2) = "")
Worksheets("Feuil3").Range(.Cells(1, ab), .Cells(1, ab + 4)).EntireColumn.Hidden = (a(i, 2) = "")
End With
Next
End Sub
A+