Volvo (and Mack)
    Volvo fault code

    Volvo Fault Code CEM-1A05: X-power supply signal too high

    CEM-1A05 on Volvo (and Mack) engines means: X-power supply signal too high.

    Code details

    Manufacturer
    Volvo (and Mack)
    Applies to
    Volvo trucks
    Fault code
    CEM-1A05
    Truck models in source
    Volvo VNL, VNR, VHD, VAH

    What to do next

    • Read active and inactive codes with the OEM service tool 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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    Source: Volvo fault code list (Whole Fleet). See also OBD-II codes.