FMI 5 — Current below normal or open circuit
The ECM is commanding a device on but almost no current flows. The circuit is open somewhere: connector, wire or the coil in the device.
Common causes
- Open winding in a solenoid, injector or actuator
- Broken wire or backed-out terminal
- Unplugged connector
- Blown fuse feeding the device
What to test, in order
- Measure coil resistance at the device and compare with spec
- Check for the supply feed at the device connector with the key on
- Continuity-check each wire end to end from the ECM connector
- Substitute a known-good device only after the wiring proves good
Codes we document with FMI 5
SPN 651 FMI 5Injector 1 circuit open · MackSPN 651 FMI 5Injector cylinder 1 circuit open · CATSPN 651 FMI 5Injector cylinder 1 circuit open · DetroitSPN 651 FMI 5Injector cylinder 1 circuit open · InternationalSPN 651 FMI 5Injector cylinder 1 circuit open · PACCARSPN 651 FMI 5Injector cylinder 1 circuit open · MERCEDESSPN 651 FMI 5Injector cylinder 1 circuit open · VolvoSPN 651 FMI 5Injector cylinder 1 circuit open · CumminsSPN 652 FMI 5Injector cylinder 2 circuit open · CATSPN 652 FMI 5Injector cylinder 2 circuit open · DetroitSPN 652 FMI 5Injector cylinder 2 circuit open · InternationalSPN 652 FMI 5Injector cylinder 2 circuit open · PACCARSPN 652 FMI 5Injector cylinder 2 circuit open · MERCEDESSPN 652 FMI 5Injector cylinder 2 circuit open · VolvoSPN 652 FMI 5Injector cylinder 2 circuit open · MackSPN 652 FMI 5Injector cylinder 2 circuit open · CumminsSPN 653 FMI 5Injector cylinder 3 circuit open · CATSPN 653 FMI 5Injector cylinder 3 circuit open · DetroitSPN 653 FMI 5Injector cylinder 3 circuit open · InternationalSPN 653 FMI 5Injector cylinder 3 circuit open · PACCARSPN 653 FMI 5Injector cylinder 3 circuit open · MERCEDESSPN 653 FMI 5Injector cylinder 3 circuit open · VolvoSPN 653 FMI 5Injector cylinder 3 circuit open · MackSPN 653 FMI 5Injector cylinder 3 circuit open · Cummins
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