Detroit DD16 GHG14 (2014-16) Fault Code: SPN 84 FMI 6 (CPC) Vehicle Speed Sensor Anti-Tamper Detection via Antilock Brake System Vehicle Speed Comparison

NOTE: This fault code indicates a missing message from the antilock brake system (ABS) module.

NOTE: If there are any battery related faults, repair those first.

PROBABLE CAUSES:
1. Vehicle speed sensor.
2. Wiring between vehicle speed sensor and ECM.
3. Engine ECM has recently been reprogrammed improperly.