If cell is colored enter a letter to it

[kisinana]

I want to look at a column and if a cell has been highlighted by a certain color then place a letter N in that cell. Also if a different color is in the column then place a LS in that cell.
I am not sure what I am missing. It looks Ok in the module and does not flag until I try to run it.

If Range("F1:F101").Cell.Interior.ColorIndex = 4 Then
    Cell.Value = "H"
    If Cell.Interior.ColorIndex = 15 Then
        Cell.Value = "LS"
    End IF