Cummins
Cummins fault code
SPN 620 / FMI 18
Cummins Fault Code 444: OEM Sensor Supply Voltage Low - Warning
444 on Cummins engines means: OEM Sensor Supply Voltage Low - Warning. The failure mode (FMI 18) is “data valid but below normal range (moderately severe)”.
Lamp: Yellow
Engine may continue to run, but must be repaired the same day.
Code details
- Manufacturer
- Cummins
- Applies to
- Cummins QS-series electronic engines
- Fault code
- 444
- J1939 SPN
- 620
- FMI
- 18 — Data valid but below normal range (moderately severe)
- J1587 PID / SID
- S232
- Engine models
- QSB, QSC, QSL9
What to do next
- Read active and inactive codes with the OEM service tool and note the occurrence count.
- FMI 18 tells the shop the type of failure to test for: data valid but below normal range (moderately severe).
- Have a heavy-duty diesel technician confirm the fault against the engine or chassis service manual before replacing parts.
Get this code diagnosed
Send one request and nearby diesel shops and mobile mechanics can quote the repair.
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Related fault codes
Source: Cummins "Diagnostic Fault Codes For Cummins Engines", publication 80-1044 Rev 5/2013, page 13. See also OBD-II codes.