bonjour,
replace ta procédure ComboBox3_Change par ceci
Private Sub ComboBox3_Change()
Dim Nom As Range, i As Long
With ThisWorkbook.Sheets("reference de camion")
For i = 2 To .[E65000].End(xlUp).Row
If .Cells(i, 2) = CStr(Me.ComboBox1.Value) And .Cells(i, 3) = CStr(Me.ComboBox2.Value) And .Cells(i, 4) = CStr(Me.ComboBox3.Value) Then
Me.TextBox1.Value = .Cells(i, 5)
'Me.TextBox2.Value = .Cells(Nom.Row, 3)
Exit For
End If
Next i
End With
End Sub