6 Series E64 650i (N62TU) CONVER
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Electrical fault:
Excitation diode defective, excitation coil has been interrupted, overvoltage due to defective governor.
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Communication failure:
Line between DME control unit and alternator defective.
An interruption or short circuit in the alternator coils will not be detected.
Oil supply
The oil condition sensor reports the engine oil level and engine oil quality back to the DME control unit. A
temperature sensor in the oil condition sensor indicates the engine oil temperature. The engine oil temperature
is used together with the coolant temperature to calculate the engine temperature.
The oil pressure is indicated by the oil-pressure switch.
The oil level is also measured for the electronic oil level check. The 2nd capacitor in the upper part of the oil
condition sensor registers the oil level. The capacitor is at the same level as the oil level in the oil sump.
As the oil level falls, the capacitance of the capacitor falls. The electronic evaluation unit creates a digital signal
from this. The DME then calculates the engine oil level.
The DME control unit activates the warning and indicator lamp in the instrument cluster via the PT-CAN (red: oil
pressure low; yellow: oil level low).
Electronic oil level check:
The dipstick now has a black handle. The engine oil level is measured by the oil condition sensor.
The measured value is displayed in the Central Information Display (CID).
The signal from the oil condition sensor is evaluated in the DME. Besides the oil level, the thermal oil level
sensor also indicates the engine oil temperature.
Condition Based Service:
In addition, the engine oil quality is measured for the Condition Based Service (CBS).
The electrical material properties of the engine oil change as the engine oil wears and ages. The changed
electrical properties of the engine oil (dielectrics) cause the capacity of the capacitor in the oil condition sensor to
change.
The electronic evaluation unit converts the measured capacity into a digital signal.
The digital sensor signal is transmitted to the DME as a statement about the condition of the engine oil.
The DME uses this to calculate the next engine oil change as part of Condition Based Service (CBS).
Engine cooling
The opening and closing of the mapped thermostat is controlled by a characteristic map. This regulating
operation can be split into 3 operating ranges:
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Mapped thermostat closed:
The coolant only flows through the engine and the coolant circuit is closed.
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Mapped thermostat open:
The entire coolant volume flows through the radiator. This results in maximum use of the available cooling
output.
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Control range of the mapped thermostat:
A proportion of the coolant flows through the radiator. The mapped thermostat maintains a constant coolant
temperature within the control range at the engine inlet.
In this operating range, the coolant temperature can now be selectively controlled with the assistance of the
mapped thermostat. This means that a high coolant temperature can be set in the part-load range of the
SBT 8-cylinder spark-ignition engine N62TU E60, E61, E63, E64, E65, E66, E70
BMW AG - TIS
06.02.2013 10:29
Issue status (12/2007) Valid only until next DVD is issued
Copyright
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