strange code????

[dieselkane]

Hey everyone, i own a 2003 6.0 psd 4x4. anyways, every time i put the truck in second gear manually (automatic trans) i get a code that pops up on the bully dog programmer that reads V3F00, what does this mean. any ideas? it only comes up if i put the truck in second manually, if the truck shifts on its own to second, no code. it comes up every time, tranny seems to shift fine, is this even a real code or something to worry about?? any help would really be appreciated. thanks