CAT 3406E (Prefix 5DS or 1LW) Fault Code: 56 PID: 231 SPN: FMI: 11 J1939 Data Link Fault
This condition indicates that the SAE J1939 Data Link is not communicating correctly.
Probable Causes:
1) ECM Connection/Harness
2) Another device on the J1939 is causing problems (ABS, VORAD, Cab controller, etc…)
3) Wiring from data link connector to ECM
