FMI 7 — Mechanical system not responding or out of adjustment
The ECM commanded a movement, the electrical side checks out, but the hardware did not move. This is a stuck or bound mechanism.
Common causes
- Soot-bound or seized actuator (EGR valve, VGT vanes, throttle)
- Binding linkage or shaft
- Insufficient supply air or hydraulic pressure to move the device
- Mechanically failed device
What to test, in order
- Command the actuator with a scan tool and watch commanded vs actual position
- Remove and inspect the mechanism for carbon binding
- Verify supply pressure (air, oil or fuel) at the actuator
- Check for a related restriction code — a plugged DPF often causes this
Codes we document with FMI 7
SPN 51 FMI 7EGR throttle valve not responding · InternationalSPN 641 FMI 7VGT / turbo actuator not responding to commands · CATSPN 641 FMI 7VGT / turbo actuator not responding to commands · DetroitSPN 641 FMI 7VGT / turbo actuator not responding to commands · InternationalSPN 641 FMI 7VGT / turbo actuator not responding to commands · PACCARSPN 641 FMI 7VGT / turbo actuator not responding to commands · MERCEDESSPN 641 FMI 7VGT / turbo actuator not responding to commands · VolvoSPN 641 FMI 7VGT / turbo actuator not responding to commands · MackSPN 641 FMI 7VGT / turbo actuator not responding to commands · CumminsSPN 2659 FMI 7Intake air heater performance · PACCARSPN 2791 FMI 7EGR valve not responding · VolvoSPN 2791 FMI 7EGR valve control not responding to commands · CATSPN 2791 FMI 7EGR valve control not responding to commands · DetroitSPN 2791 FMI 7EGR valve control not responding to commands · InternationalSPN 2791 FMI 7EGR valve control not responding to commands · PACCARSPN 2791 FMI 7EGR valve control not responding to commands · MERCEDESSPN 2791 FMI 7EGR valve control not responding to commands · MackSPN 2791 FMI 7EGR valve control not responding to commands · CumminsSPN 3556 FMI 7Hydrocarbon doser performance · PACCARSPN 3556 FMI 7Aftertreatment fuel doser not responding · CATSPN 3556 FMI 7Aftertreatment fuel doser not responding · DetroitSPN 3556 FMI 7Aftertreatment fuel doser not responding · InternationalSPN 3556 FMI 7Aftertreatment fuel doser not responding · MERCEDESSPN 3556 FMI 7Aftertreatment fuel doser not responding · Volvo
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