Troubleshooting

Cummins Fault Code 3868 (SPN 3364 FMI 9) on B6.7 CM2350: What It Means and How to Chase It

Cummins fault code 3868 (SPN 3364, FMI 9/9) on a B6.7 CM2350 means the DEF quality sensor has gone a period of time without producing a concentration value, and the ECM has lost communication with it over the J1939 data