It is a failure of the communication system on the truck (called a bus). The cause can include computers, wires, fuses, grounds, etc.
Trouble code P0234 means:Engine overboost condition
#2 warm air heater relay wiring fault
P1693 : Dtc detected in the companion module. You need to check the Ecm and Pcm for codes. Which ever did not have p1693 will have a code.
Low oil pressure
Camshaft position sensor circuit malfunction.
Trouble code P0177 means:Fuel composition sensor circuit range/performance
Trouble code P0483 means: Fan Performance
Trouble code P1693 means: A companion DTC was set in both the ECM and PCM
Trouble code P0573 means:Cruise control/brake switch A circuit high
my book says code 0123 THROTTLE/PEDAL POSITION SENSOR/SWITCH A CIRCUIT HIGH INPUT
P1693 means that there is a code in the companion module. The pcm and ecm are the companion modules.
The U3FFF code on a Dodge 2500 diesel typically refers to an issue related to the exhaust gas recirculation (EGR) system or the diesel particulate filter (DPF). This code may indicate that the vehicle's computer has detected a fault in the emissions control system, which can affect engine performance and emissions compliance. It's advisable to use a diagnostic scanner to confirm the exact issue and consult a mechanic for proper diagnosis and repair.