I have a friend at work who just bought a new truck and now he is having problems with it. I got these codes off of the odometer today. P0122, P1682, P1693, P1694. I know what the 122 and the 1682 codes are so i had him reset his APPS, and the charging system is fine. So my question is what are these other rwo codes? P1693 DTC from ecm or pcm and P1694, no CCD recieved from ecm. He said he was climbing a hill last night and the power just died out and he was thinking VP, but i was thinking gelling because it was -5 to 8 degrees all day. i'm going to check his pressure this weekend. FYI this truck is all stock.