SPN 1347 FMI 7 indicates the fuel delivery system was commanded but is not responding mechanically or hydraulically as expected. Seized pump, open power path, failed relay contacts, severe restriction, empty supply, and control circuit issues are the primary causes. Command present with voltage present but pressure or flow absent points to a mechanical pump or hydraulic restriction.

Confirm relay output voltage under command and ground path at the pump before pump condemnation. Command present with voltage present but pressure or flow absent points to mechanical pump or hydraulic restriction.

Verify command is present. Measure voltage at pump connector under command — voltage drop under load identifies power path issues. Check outlet pressure or flow with voltage confirmed. Inspect for restriction if voltage and command are present but flow is absent. Replace pump assembly only after electrical and path proof.