3 Series E91 320i (N46T) TOUR
accordingly. If necessary, the coolant pump can even be switched off altogether, for example to heat up the
coolant quickly during the warm-up phase.
If the engine is not running but very hot, the coolant pump will also work while the vehicle is out of use. Cooling
output can thus be called up regardless of engine speed.
The heat management now permits various characteristic maps to be used as a basis for controlling the coolant
pump, over and above the map thermostat. In this way, the engine control unit can adapt the engine temperature
to the driving characteristics.
The engine control unit regulates the following temperature ranges:
•
112
°
C = Economy
•
105
°
C = Normal
•
95
°
C = High
•
80
°
C = High and regulation by the map thermostat
If the vehicle handling causes the engine control unit to detect the economical operating range Economy, the
DME regulates to a higher temperature (112 C).
In this temperature range, the engine is operated with a relatively fuel requirement. The friction inside the engine
is reduced at higher temperature. The temperature increase thus favours lower fuel consumption in the low load
range.
In the High and regulation by the map thermostat mode, the driver wants to use optimised power output
development of the engine. To achieve this, the temperature in the cylinder head is lowered to 80
°
C. This
lowering leads to a better cylinder filling, which leads in turn to an increase in engine torque. The engine control
unit can now regulate a certain operating range, adapted to the relevant driving situation. This makes it possible
to use the cooling system to influence consumption and performance.
Active air flap control
Active air flap control regulates the air supply for the engine and assemblies cooling system by only opening the
air flaps as they are needed.
Notes for service staff
Service staff should note the following points:
-
General notes: [more ...]
-
Diagnosis: ---
-
Encoding/programming: ---
Subject to change.
SBT N52 engine E60, E61, E63, E64, E65, E66, E70, E81, E82, E83, E85, E86, E87, E90,
BMW AG - TIS
27.01.2013 10:23
Issue status (12/2007) Valid only until next DVD is issued
Copyright
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