3 Series E46 316i (M43TU) SAL
Signals from the throttle-valve potentiometer (engine load signal), from the wheel speed sensors (road
speed) and the brake-light switch (brake in operation) allow the SMG control unit program to recognise
when the vehicle is driving downhill. If road speed increases, the SMG control unit will shift down a gear to
maintain and increase the engine's braking effect.
•
Braking deceleration and automatic downshift
The SMG control unit recognises braking deceleration from the brake-light switch, the wheel speed sensors
and the accelerator pedal setting. The SMG control unit shifts down according to road speed to maintain the
engine's braking effect. As this happens, several gears may be skipped. The correct gear is automatically
selected when the vehicle accelerates again.
•
Manual intervention by the driver in automatic mode
If the driver moves the gear lever or the gearshift paddles while automatic mode is active, the system will
automatically change to manual mode. Automatic mode must be reselected by the driver.
Acceleration assistance (race-start function)
Conditions for acceleration assistance:
•
High-grip road surface
•
Dynamic Stability Control DSC deactivated (DSC button pressed for longer than 3 seconds)
•
SPORT button pressed
Acceleration assistance allows optimum vehicle acceleration from standstill, on a par with motor racing
standards. Normally, the clutch engages at approx. 1300 rpm. With the acceleration assistance, the engine
speed is increased to approx. 4000 rpm before the SMG closes the clutch. To make use of this, the driver
merely has to depress the accelerator pedal quickly and completely (kickdown). Forced upshift in manual mode
(only with race-start function) makes sure that the engine is unable to reach a critical speed. The race-start
function is deactivated by cancelling the kickdown function via the accelerator pedal position, by deactivating the
Dynamic Driving Control FDC with the SPORT button or by activating DSC.
Rocking free, e.g. from snow
To rock the vehicle free, e.g. from snow, the gear lever can be moved rapidly from the 1st gear position to "R"
and vice versa. The gearshift must be completed within the space of 0.8 seconds as the gear lever lock (shift-
lock) will otherwise be activated.
Vehicle standstill
If the SMG control unit recognises a vehicle standstill from the pedal position transmittor and the engine speed,
the clutch will be opened and 1st gear engaged, regardless of the driving program (manual mode or cruise
mode).
If the engine is running and the driver's door opened, a warning is given that a drive position is engaged
(warning signal 9 times in succession). The "N" symbol flashes (9 times) in the instrument cluster. If neither the
pedals, the gearshift paddles nor the gear lever are moved, the gear is automatically cancelled after approx.
2 seconds.
Gear lever position neutral and ignition off
If the gear lever is in neutral and the ignition is switched off, the "N" symbol flashes in the program indicator in
the instrument cluster. The standard acoustic generator in the instrument cluster gives off a warning signal for
approx. 9 seconds. The acoustic generator is actuated by the SMG control unit.
Fault display, GMG warning lamp and emergency program
SBT Sequential manual transmission SMG, based on GS6- 37BZ E46
BMW AG - TIS
19.01.2013 20:44
Issue status (12/2007) Valid only until next DVD is issued
Copyright
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