04 Ram 1500 SLT 4.7 CEL is on, no code and won't start

I have a 2004 Dodge Ram 1500 4.7 SLT, this past Thursday when I left work
my check engine light came on but the truck was running fine. I didn't have
time that night to stop and have someone pull the code. The next
day(Friday) I started my truck and the cel was still on but again everything
was working fine. I went to work and was planning on stopping by a auto
parts store to have them pull the code but my truck wont start. It cranks but
doesn't turn over, I was able to get ahold of a obd2 reader but it's not reading
any codes either. I'm trying to figure out what would throw a cel but prevent
the truck from starting. I've checked relays, fuses, battery voltage,
connections, and tried a pcm reset but nothing still has the cel on and wont
pull code.  My coworkers said it sounds like the fuel pump, but my son said
he heard a noise(hum/buz) near the fuel tank when I turned the key to the on
position.     What else should I look for?