3 Series E46 318ti (N42) COMP
The electric throttle-valve actuator is electrically opened or closed by the DME control unit.
With Valvetronic, the throttle-valve actuator is activated for the following functions:
•
Engine start (warmup), not N45TU2/N46TU2
•
Idle speed control
•
Full load operation
•
Emergency operation
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2 VANOS solenoid valves
The purpose of the variable camshaft control is to increase torque in the low and medium engine speed ranges.
A VANOS solenoid valve controls a VANOS adjustment unit on the intake end and the exhaust end.
The VANOS solenoid valves are controlled by the DME control unit.
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Fuel pump relay
The fuel pump relay controls the electric fuel pump.
The DME control unit monitors the activation of the fuel pump relay. The fuel pump relay is actuated by a safety
circuit,only when the engine is running and shortly after terminal 15 ON to build up pressure (fuel pump feed).
> E81, E87, E90, E91, E92, E93
The fuel-pump relay is in the junction box.
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4 injectors
During fully sequential fuel injection, each injector is controlled by the DME control unit via its own final stage.
During this process, the fuel injection period of the specific cylinder is adjusted to suit the operating conditions
(engine speed, load and engine temperature).
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Fuel evaporation control valve
The fuel evaporation control valve regenerates the activated carbon filter using scavenging air. The scavenging
air which is drawn through the activated carbon filter is then enriched with hydrocarbons and fed to the
combustion engine.
In a current-free state, the fuel evaporation control valve is closed. This prevents the ingress of fuel vapour from
the activated carbon filter into the inlet pipe when the engine is switched off.
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4 ignition coils with overload-protection relay
The ignition coils are activated by the DME control unit. From ignition overload-protection relay receive the
ignition coils terminal 30.
On the N45TU2/N46TU2, there is no relief relay for reliable engine OFF. The ignition coils receive their power
supply via terminal 87.
The function "reliable engine OFF" is internally assumed by the DME control unit via an additional independent
current path. The CAS control unit supplies the input signal.
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Mapped thermostat
The opening and closing of the map thermostat (N46 only) is controlled by a characteristic map.
The mapped thermostat ensures that within its control range a constant coolant temperature is maintained at the
engine inlet.
For driving conditions with low loads, the mapped thermostat sets a high coolant temperature (efficient
consumption). For full loads or higher engine speeds, the coolant temperature is reduced to protect the
components.
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Secondary air pump relay and secondary air pump (for EURO 4 exhaust emissions regulations)
> E46, E83, E85
The secondary air pump relay activates the secondary air pump shortly after the engine has been switched on.
The switch-on period depends on the following criteria: engine temperature, load and engine speed.
SBT Engine control for N45, N46 E46, E60, E81, E83, E85, E87, E90, E91, E92, E93
BMW AG - TIS
12.02.2013 21:13
Issue status (12/2007) Valid only until next DVD is issued
Copyright
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