MID 128, PPID 6 Key off input sensor
FMI 4 – Voltage below normal or shorted to lower voltage
Fault code explanation: Faulty circuit.
Fault indication: DCU: Engine warning in DCU display.
CIU: Flash code
Flash code
Electrical fault: 4.8 (EMS)
Value fault: None (EMS)
Electrical fault: 5.3 (CIU)
Value fault: None (CIU)
Symptom: Engine can only be stopped using the auxiliary stop.
Conditions for fault code: Engine can only be stopped using the auxiliary stop.
Possible reason: Short circuit between the engine stop signal in engine connector and battery
negative.
Suitable action: 1 Check the stop signal cable between the engine control unit A27 and
the CIU/DCU.
Circuit description
The stop
input signal to the engine control unit pin A27
can have one of two signal levels, high/low. The A27
stop input on the EMS2 can be set via a parameter in
Vodia to work in one of two ways.
Either the EMS2 stop input is set to “energized to run”
which means that the stop input signal to the EMS2 pin
A27 must be high in order for the engine to be able to
run or the EMS2 stop input is set to “energized to stop”
which means that the stop input signal on the EMS2
pin A27 must be high in order for the engine to stop.
In the first case the stop input signal level has to be low
to shut down the engine.
In the second case the stop input signal level has to be
high to shut down the engine.
Measurements
Checking stop signal cable between ECU and CIU/
DCU page 168
30-2 Fault Tracing
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