Is the truck low on power?
It is a low boost code, so many people will automatically tell you to clean the turbo, which it may still need but there are two other things I would try first.
Find the rubber hose that connects to the intake manifold, it's on the passenger side of the intake manifold. Pull it off, make sure it's clean and free of crud.
Next would be to disconnect the exhaust system in FRONT of the cat (bypass the cat) and test drive. I've heard of them plugging the cats (not sure how on these honestly) and it would cause this too.
Next I would pull the EPB tube and sensor, clean both really well.
Then it would be a turbo cleaning DTS Articles - Turbocharger Reconditioning
Those should get you back going again.