I'm not showing a P1798 for your truck but the P1698 is for a loss of communication between the PCM and TCM. This will be either a wiring/connection problem or a TCM issue. You can try unplugging the connectors and checking for corrosion at the TCM and PCM connectors. If this doesn't remedy the problem, it's time to break out a lab scope for some data bus diagnostics.
after reading up on google, turns out it was set off due to my remote starter. i read that disconnecting the battery for 10 minutes should reset it and it did. took it for a short drive and its still off. ill update if it comes back