Good Morning. I have a basic Actron OBD 2 tool that reads and resets codes, it gave me a code error of P0401 Exhaust Gas Recirculation Flow Malfunction. I then had a warning sign that came up on my display that had a arrow type symbol. When I looked at my 2004 Turbo Diesel 6.0 liter user Manual it said this symbol indicates a dirty air cleaner. I replaced the air cleaner and reset the code with the Actron. The code was reset and shows no codes but the display light is still on. Maybe I need to buy a advanced scanning tool that will help me with my problems. Any recommendations?