MID 128, PID 153 Crankcase
pressure
FMI 0 – Data valid but above normal operational range
Fault code explanation: Crankcase pressure is rising too fast.
Fault indication: DCU: Engine warning in DCU display.
CIU: Flash code
Flash code
Electrical fault: 7.8
Value fault: 7.7
Symptom: The engine is shut down if the engine protection parameter is activated.
Conditions for fault code: Crankcase pressure rises too fast.
Possible reason: • Blocked crankcase ventilation.
•
Faulty crankcase pressure sensor.
•
Worn or damaged cylinder liners, piston or piston rings.
Suitable action: 1 Check whether the crankcase ventilation is blocked. Clean the crank-
case ventilation system.
2 Check all cable and connectors between the EMS2 and the crankcase
pressure sensor.
3 Check the crankcase pressure sensor.
4 Control measure the crankcase pressure.
5 Check whether cylinder liner, piston or piston rings are worn or dam-
aged.
FMI 3 – Voltage above normal or shorted high
Fault code explanation: Faulty sensor / Fault in sensor circuit
Fault indication: DCU: Engine warning in DCU display.
CIU: Flash code
Flash code
Electrical fault: 7.8
Value fault: 7.7
Conditions for fault code: The voltage on pin B28 in the engine control unit exceeds 4.78 Volt.
Possible reason: • Short
circuit between sensor signal cable and 5V supply or battery volt-
age to crankcase pressure sensor.
•
Open circuit in the sensor negative cable.
• Faulty sensor.
Suitable action: 1 Check the cable harness between the crankcase pressure sensor and
the EMS2.
2 Check the contact pressure in socket 18 in the engine connector B.
3 Check the sensor.
30-2 Fault Tracing
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