Excel VBA - Cell color Change

Question

I am trying to write a macro that changes colors based on a value in Column L. If the cell in Column L is YES, then Hightlight Column B cell in Red. However, the Macro below doesn't work or fail. It runs but does nothing.

   Sub ColorMeElmo()
   Dim i As Long, r1 As Range, r2 As Range
   For i = 2 To 5
   Set r1 = Range("L" & i)
   Set r2 = Range("B" & i & ":B" & i)
   If r1.Value = "YES" Then r2.Interior.Color = vbRed
   Next i
   End Sub 

Answer 1

Put this in Sheet you want to watch.

Private Sub Worksheet_Change(ByVal Target As Range)
    Dim CCell As Range
    Dim sht As Worksheet
    Set CCell = Range("L:L")
    Set sht = Worksheets("Sheet1") 'EDIT
    If Target.Count = 1 Then
        If Not Application.Intersect(CCell, Range(Target.Address)) _
            Is Nothing Then
                If Target.Value = "YES" Then
                    sht.Cells(Target.Row, 2).Interior.Color = RGB(255, 0, 0)
                End If
        End If
    End If
End Sub

Answer 2

Private Sub Worksheet_Change(ByVal Target As Range)
    Dim CCell As Range
    Dim sht As Worksheet
    Set CCell = Range("L:L")
    Set sht = Worksheets("SheetName") 
    If Target.Count = 1 Then
        If Not Application.Intersect(CCell, Range(Target.Address)) _
            Is Nothing Then
                If Target.Value = "YES" Then
                    sht.Cells(Target.Row, 2).Interior.Color = RGB(255, 0, 0)
                End If
        End If
    End If
End Sub