Detroit Diesel
    Detroit flash code

    Detroit Flash Code 1615: Reserved Monitoring Unit For Temperature Diagnostics, Circuit Failed High MU_ISP_T_TBD1_SRH

    1615 on Detroit Diesel engines means: Reserved Monitoring Unit For Temperature Diagnostics, Circuit Failed High MU_ISP_T_TBD1_SRH.

    Code details

    Manufacturer
    Detroit Diesel
    Applies to
    Detroit DDEC VI (legacy flash codes)
    Fault code
    1615

    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

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    Related fault codes

    Source: Detroit DDEC VI legacy fault codes (Detroit ANZ). See also OBD-II codes.