MID 128, PID 45 Inlet air heater
status
FMI 3 – Voltage above normal or shorted high
Fault code explanation: Faulty sensor / Faulty sensor circuit
Fault indication: DCU: Engine warning in DCU display.
CIU: Flash code
Flash code
Electrical fault: 5.4
Value fault: None
Symptom: Preheat relay never activated. White smoke for cold start.Start problems in
cold climate.
Conditions for fault code: The voltage on pin B25 or on pin B7 on the EMS2 deviates from normal
voltage value.
Possible reason: Short circuit to battery voltage in cable harness between EMS2 and preheat
relay.
Suitable action: 1 Check all connections on the preheat relay and all cables between
EMS2 and preheat relay.
FMI 4 – Voltage below normal or shorted to lower voltage
Fault code explanation: Faulty sensor / Faulty sensor circuit
Fault indication: DCU: Engine warning in DCU display.
CIU: Flash code
Flash code
Electrical fault: 5.4
Value fault: None
Symptom: Induction air is hot. Preheat relay is impossible to turn off. Preheat fuse will
break.
Conditions for fault code: The voltage on pin B25 or on pin B7 on the EMS2 deviates from normal
voltage value.
Possible reason: Short circuit to battery negative in cable harness between EMS2 and preheat
relay.
Suitable action: 1 Check all connections on the preheat relay and all cables between
EMS2 and preheat relay.
30-2 Fault Tracing
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