Cummins
    Cummins fault code
    SPN 703 / FMI 3

    Cummins Fault Code 529: Auxiliary Input/Output #3 Circuit - shorted high

    529 on Cummins engines means: Auxiliary Input/Output #3 Circuit - shorted high. The failure mode (FMI 3) is “voltage above normal, or shorted to high source”.

    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
    529
    J1939 SPN
    703
    FMI
    3 — Voltage above normal, or shorted to high source
    J1587 PID / SID
    S051
    Engine models
    QSB, QSC, QSL9, QSM11, QSX15, QSK19, QSK23, QST30
    QSK45/60/78 severity level
    QSK45: 2 • QSK60: 2 • QSK78: 2

    What to do next

    • Read active and inactive codes with the OEM service tool and note the occurrence count.
    • FMI 3 tells the shop the type of failure to test for: voltage above normal, or shorted to high source.
    • 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 15. See also OBD-II codes.