Detroit Diesel
    Detroit flash code

    Detroit Flash Code 1242: Injector Cylinder #1 Needle Control Valve Abnormal Operation

    1242 on Detroit Diesel engines means: Injector Cylinder #1 Needle Control Valve Abnormal Operation.

    Code details

    Manufacturer
    Detroit Diesel
    Applies to
    Detroit DDEC VI (legacy flash codes)
    Fault code
    1242

    What to do next

    • Read active and inactive codes with the OEM service tool (Detroit Diesel Diagnostic Link) and note the occurrence count.
    • 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: Detroit DDEC VI legacy fault codes (Detroit ANZ). See also OBD-II codes.