FMI 7 – Mechanical system not responding properly
Fault code explanation: Fault in the injection system.
Fault indication: DCU: Engine warning in DCU display.
CIU: Flash code
Flash code
Electrical fault: 7.1–7.6
Value fault: None.
Symptom: Faulty unit injector is shut off, engine runs on 5 cylinders. Limp home on rest
of unit injectors. Engine performance is reduced. Abnormal sound.
Preconditions: NOTICE! Identify which injector by the SID number.
Conditions for fault code: Injector activated and cylinder balancing above limit.
If a fault code is set when the engine has an unsymmetrical load it can not
be rectified.
At idle speed the engine control unit is trying to compensate for
uneven running by adding more or less fuel to the injectors, cylinder balanc-
ing. If the engine load is too unsymmetrical the compensation is not enough
and a fault code will be set.
Possible reason: • Unsymmetrical load of the engine.
• Poor / uneven compression.
• Faulty injector.
Suitable action: 1 Clear the fault code with the Vodia tool. Let the engine run at idle speed
without any load and see if the faultcode reappear.
2 Perform test of cylinder compression using the VODIA tool.
3 Change only the faulty injector.
FMI 12 – Faulty device or component
(Low unit injector hold current)
Fault code explanation: Fault in the injection system.
Fault indication: DCU: Engine warning in DCU display.
CIU: Flash code
Flash code
Electrical fault: 7.1–7.6
Value fault: None.
Symptom: Faulty unit injector is shut off, engine runs on 5 cylinders. Limp home on rest
of unit injectors. Engine performance is reduced. Abnormal sound.
Preconditions: NOTICE! Identify which injector by the SID number.
Conditions for fault code: Low injector hold current. Injector activated.
Possible reason: Intermittent fault.
Suitable action: 1 Check the cables between the injector and the engine control unit.
2 Check
the
contact pressure in all sockets regarding the unit injectors in
engine connector A.
3 Check the cable connection to the injector.
30-2 Fault Tracing
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