Reading Ford Powertrain Codes

Hello all,

I'm getting the perverbial flashing "O/D" light on my '02 Explorer.
The tranny seems to be working fine, but the day may be comming...
I've got an ELM327 scan tool, but can't pull the tranny code. Have
tried most of the ELM-based software and none of them will even detect
that there is a pending code. I can clear the code just fine - just
can't read it. Has anyone had problems getting the powertrain codes
out? Preferrably using one of the ELM scanners.

Thanks for any replies.
Dan