Applying code to entire column

Hi Guys,

I'm pretty new to vba, and i've written some code which works fine apart from i need it to run down an entire column, as it stands it's just one cell.

Here's a section of the code, it is considerably longer but it's pretty much repeating the same format just looking for different data.

Sub subConfig()
Dim subConfig As String
subConfig = "AB4"

    If Range("K4").Value = "CD" And Range("L4").Value = "1" Then
        Range(subConfig).Value = "5"
    ElseIf Range("K4").Value = "CD" And Range("L4").Value = "2" Then
    Range(subConfig).Value = "D"
    ElseIf Range("K4").Value = "CD" And Range("L4").Value = "3" Or Range("L4").Value = "4" Then
    Range(subConfig).Value = "H"
    ElseIf Range("K4").Value = "CD" And Range("L4").Value = "5" Then
    Range(subConfig).Value = "G"
    ElseIf Range("K4").Value = "CD" And Range("L4").Value = "6" Or Range("L4") = "7" Or Range("L4") = "8" Then
       Range(subConfig).Value = "R"
    ElseIf Range("K4").Value = "CD" And Range("L4").Value = "9" Or Range("L4") = "10" Or Range("L4") = "11" Or Range("L4") = "12" Then
       Range(subConfig).Value = "T"

I've tried a few a couple of ways to apply it to the column but it just seems to crash or error. Any help is hugely appreciated