Volvo Engine D13F Fault Code: PID 251 FMI 2 Clock

CONTROL UNIT:
Engine ECU

DETECTION CONDITIONS:
The engine control unit (E-ECU) registers that time data is missing or is not arriving often enough.

SYMPTOM:
Limp home function activated.

POSSIBLE CAUSES:
1. Both data buses, J1939 and J1708/ J1587 not functional at the same time.
2. Open circuit on bus communication (cable harness).