Private Sub Worksheet_Change(ByVal Target As Range)
If Target.Cells.Count > 1 Then Exit Sub ' More than one cell chnaged. Get Out.
'This makes sure that only one cell is passed to the lookup - you could modify the code to send a message that tells the user to only change one value at a time now it just stops
If Not Application.Intersect(Target, Me.Range("A1:C10")) Is Nothing Then
' Target is within the range A1:C10 - you need to adjust this range to match your area of interest.
Application.EnableEvents = False 'To make sure you dont get caught in an endless loop
Target = Application.WorksheetFunction.VLookup(Target.Value, Range("I2:J6"), 2) 'You need to change I2:J6 to match where your table is
Application.EnableEvents = True 'Turns event procedures back on for the next change
Else
' No cell of Target in in the range A1:C10. Get Out.
Exit Sub
End If
End Sub