Did all these DTC's all show up at once? If so, and in general, when a bunch of unrelated codes appear out of nowhere, chances are the DTC's are not valid, but another fault in the system is causing erroneous coding. This can usually be traced back to a single event, such as bad battery(ies), flaky alternator, improper jump-start, system short, excessive voltage (such as improperly connected multiple batteries), loss of a ground (lose a bonding strap, and the system will ground through other components, including the PCM), or collision damage. The PCM is also suspect. They don't fail often, but they do. Often when in the process of catastrophic failure, the PCM will dump erroneous codes, or seemingly erroneous codes that may be assembly line checks that are not listed, such as the P1291, which has no reference to the truck you're working on.
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