Yep, it was the PDC.
I have a 2004 Dodge 1500 Hemi, and I had the same problem with the drivers side low beam not working, but both Hi-beams worked just fine.
Took it to the dealer and paid to have him trouble shoot it....after $95.00, he said the PDC was bad, and it woud be about $500.00 to order a new one and install it.
I went to the wrecking yard, got a PDC with the computer module for $175.00, and installed it....Voila....problem fixed.
BTW, I was asked by the dealer if I had "Washed" my Engine....yep, sure did....and it did start doing this, right after that....hmmmmmm
Last edited by CoachGary; 03-29-2011 at 10:27 PM.
Reason: Add one more thing.