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
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