© Scania CV 2011
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Limp home mode
If there is a fault on the normal accelerator pedal or if CAN communication is
interrupted, the following limp-home option is available:
CAN fault or accelerator pedal fault (both signal and idling switch):
- The accelerator pedal value is 0 % and the engine is running at normal
idling speed.
- The accelerator pedal value is 0% and the engine is running at fixed
raised idling speed (750 rpm) if this function is activated.
Accelerator pedal malfunction but the idling switch is working:
- The accelerator pedal value can be increased slowly between 0% and
50% by using the idling switch.
CAN fault:
- The engine is switched off if the shutdown function is activated.
Coolant temperature
Normal coolant temperature when the engine is running should be 70-90°C.
The EMS/S6 control system has the following alarm levels for elevated
coolant temperatures:
The basic values are 95°C for the lower level and 105°C for the higher level.
- If the temperature is over 95°C for a certain period (1 second), S6 will
send a CAN message which switches on the warning lamp and
diagnostics lamp via the coordinator.
- If the temperature exceeds 95°C and torque reduction is activated, the
warning lamp and the diagnostics lamp will come on and the amount of
fuel will be reduced to 70%. A fault code is generated in the control unit.
- At temperatures exceeding 105°C and with engine shutdown activated,
the warning lamp and diagnostics lamp come on and the engine is
switched off. If override is activated, only torque reduction works. A
fault code is generated in the control unit.
After an alarm, approved values should be registered for more than 2 seconds
to reset the alarm.
Excessively high coolant temperature can damage the engine.
If run for extended periods under an extremely light load, the engine may
have difficulty in maintaining normal operating temperature. However, the
temperature will rise to a normal level again when the load on the engine is
increased.
