2004 BMW 325I Brake system

71
instance, downshifts that would
result in excessive engine speed can-
not be executed
>When you brake the car to a stop, the
transmission automatically shifts
down to first gear
>As speed diminishes the transmission
will shift down automatically, without
any action on your part, just before
the vehicle slows to below each
gear's minimum speed.
Available displaysR N 1 2 3 4 5 6
D1 D2 D3 D4 D5 D6
The currently engaged gear, the
selected mode, and any malfunctions
are displayed in the instrument cluster.Indicator lamp
If the indicator lamp comes on,
there is a malfunction in the
transmission system.
All selector lever positions can still be
engaged, but in the forward driving
positions only certain gears are actually
available when the vehicle is driven.
Avoid extreme loads and proceed to
the nearest BMW center.
For information on jump-starting and
towing the vehicle, refer to page 153.Warning toneAn acoustic signal sounds if the SMG
gearbox overheats; if possible you
should either stop or increase your pull-
away speed so that the system can
cool down.
Sequential manual gearbox SMG*
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Available displaysP R N D SD M1 M2 M3 M4 M5Electronic transmission control
module
If the indicator lamp comes on,
there is a malfunction in the
transmission system.
Bring the vehicle to a stop. Move the
transmission selector lever to P. Set the
parking brake and turn the engine off –
ignition key to position 0.
Wait a few seconds, then start the
engine.
If the indicator lamp goes out after a
few seconds, normal transmission per-
formance has been restored. You may
continue to drive as usual.
If the indicator lamp does not go out,
you can place the selector lever in all
positions. However, the vehicle will now
only operate in 3rd and 4th gear.
If this happens, avoid extreme engine
loads and consult the nearest autho-
rized BMW center.
Never work in the engine com-
partment when a drive gear – for-
ward or reverse – is engaged. If you do
this, the vehicle could move.<
For towing or jump-starting, refer to the
information beginning on page 153.
Automatic transmission with Steptronic*
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The speed stored in memory is deleted.To store and maintain speed or to
acceleratePress button + briefly:
The system stores and maintains the
current vehicle speed. Every time you
tap the button, the speed increases by
approx. 0.6 mph / 1 km/h.
Press and hold button +:
The vehicle accelerates without pres-
sure on the accelerator pedal. When
you release the button, the system
stores and maintains the current speed.
If on a downhill gradient the
engine braking effect is not suffi-
cient, the controlled speed can be
exceeded. Speed can drop on uphill
grades if the engine output is insuffi-
cient. When cruise control is active, every tap
of the button reduces the speed by
approx. 0.6 mph / 1 km/h.
Press and hold button –:
With the cruise control active, the sys-
tem automatically reduces the throttle
opening to slow the vehicle. When you
release the button, the system stores
and maintains the current speed.To interrupt the cruise controlWhen the system is activated, press the
button. The indicator lamp stays on.
You can use the cruise control again
whenever you want by calling up the
speed that was stored last.
In addition, cruise control is interrupted
automatically:
>When the brakes are applied
>When you apply pressure to the
clutch pedal, or when you move the
automatic transmission selector lever
from D to N
>If you exceed or fall below the pro-
grammed speed for an extended
period – by depressing the accelera-
tor, for example.
To recall the stored settingPress button:
The vehicle accelerates to and main-
tains the last speed stored.
Cruise control*
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Dynamic Stability Control (DSC)The conceptDSC maintains vehicle stability, even in
critical driving situations.
The DSC is operational every time you
start the engine.
DSC incorporates the Dynamic Traction
Control (DTC) and Cornering Brake
Control (CBC) functions.
For information on vehicles with all-
wheel drive, refer to page 89 ff.Indicator lamps
The indicator lamp in the instru-
ment cluster goes out shortly
after the ignition has been
switched on; refer to page 19.
>The indicator lamp flashes: DSC is
actively controlling drive torque and
braking intervention
>The indicator lamp stays lit: DSC has
been switched off with the button;
DTC and DBC are operational. DTC
control intervention is not indicated.
The indicator lamp and the
brake warning lamp continu-
ously light up in yellow:
The DSC, DTC and DBC have
been switched off manually or
there is a system malfunction.
The vehicle will remain completely
operational, however, without DSC. In
the event of a fault, please consult your
BMW center.
Indicator and warning lamps for
Canadian models.
Deactivating the DSC/activating
the DTCPress the DSC button briefly; the indi-
cator lamp comes on and stays on.
DSC is deactivated; DTC is operational.
In the following rare situations, it may
prove useful to activate the DTC for a
brief period:
>When rocking the vehicle or starting
off in deep snow or on loose surfaces
>When driving on snow-covered
grades, in deep snow, or on a snow-
covered surface that has been
packed down from being driven on
>When driving with snow chains.
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Under these special circumstances
traction is increased by deactivating the
control systems that enhance traction
under normal conditions.Deactivating the DSC and the
DTCPress the DSC button down for at least
3 seconds; the indicator lamp and the
yellow brake warning lamp will remain
on continuously.
The systems for enhancing stability and
traction are deactivated, and there is no
active braking intervention or torque
control.
To maintain vehicle stability,
always drive with the DSC acti-
vated whenever possible. cator lamp or the indicator lamps will go
out. DTC is deactivated.
The laws of physics cannot be
repealed, even with DSC. An
appropriate driving style always
remains the responsibility of the driver.
We therefore urge you to avoid using
the additional safety margin of the sys-
tem as an excuse for taking risks.
Whenever the DTC is activated, the
DSC is switched off and DTC performs
minor stabilizing intervention.
Do not make any modifications to the
DSC system. Allow only authorized
technicians to perform service proce-
dures on the DSC.<
Dynamic Stability Control (DSC)

89
Dynamic Stability Control (DSC) – 325xi, 330xiThe conceptDSC maintains vehicle stability, even in
critical driving situations.
The DSC is operational every time you
start the engine.
DSC includes the Automatic Differential
Brake (ADB-X) and Cornering Brake
Control (CBC) functions.Indicator lamps
The indicator lamp in the instru-
ment cluster goes out shortly
after the ignition has been
switched on; refer to page 19.
>The indicator lamp flashes: DSC is
actively controlling drive torque and
braking intervention
>The indicator lamp stays lit: DSC has
been switched off with the button;
ADB-X is operational. ADB-X control
intervention is not indicated.
If the indicator lamp fails to go out
when you press the DSC button,
this indicates a malfunction in the DSC
and ADB-X systems; the system is
deactivated, and the stability enhance-
ment functions are no longer avail-
able.<
The vehicle will remain completely
operational, however, without DSC. In
the event of a fault, please consult your
BMW center.
To deactivate DSCPress the DSC button; the indicator
lamp comes on and stays on.
DSC is now off, and ADB-X reverts to
its maximum torque-transfer mode.
In the following exceptional circum-
stances, it may be effective to deacti-
vate the DSC for a short period:
>When rocking the vehicle or starting
off in deep snow or on loose surfaces
>When driving with snow chains.
To maintain vehicle stability,
always drive with the DSC acti-
vated whenever possible.<
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Hill Descent Control (HDC)*The conceptBy reducing the vehicle's speed on
steep downhill stretches, HDC main-
tains predictable vehicle handling
response to provide you with control of
your BMW during extreme descents.
The vehicle slows to a pace just slightly
faster than walking speed.
HDC is available for activation at vehi-
cle speeds below approx. 22 mph /
35 km/h. When driving down steep
hills, the vehicle reduces speed auto-
matically down to about double walking
speed – approx. 7.5 mph / 12 km/h –
and then maintains this speed at a con-
stant.
You can use the accelerator or brakes
to vary this speed within a range from
approx. 3 mph / 5 km/h to approx.
15 mph / 25 km/h.
In conjunction with the multifunction
steering wheel, you can use the +/–
button to set the cruise control to a tar-
get speed in the range from
approx. 3 mph / 5 km/h to approx.
15 mph / 25 km/h.
HDC is automatically deactivated once
vehicle speed again exceeds approx.
37 mph / 60 km/h.
To activate the systemPress the HDC button; the green indi-
cator lamp integrated within the button
comes on.
The indicator lamp flashes whenever
the system is actively intervening to
control your speed with automatic
brake applications.To deactivate the systemPress the button again, the indicator
lamp goes out.
HDC is automatically deactivated once
the vehicle accelerates to more than
37 mph / 60 km/h, as well as whenever
you switch off the ignition.
To use HDCVehicles with manual transmission:
You should always ensure that either
reverse or first gear is engaged before
using HDC, as the engine's braking
effect is most pronounced in these
gears, and only reduced engine braking
is available in higher gears.
Vehicles with automatic transmission:
HDC is available for use in all ranges.System malfunctionsAre signaled by the indicator lamp,
which responds to problems by going
out while HDC is in operation or by fail-
ing to come on when you activate the
system:
HDC has been temporarily deactivated
as a result of high brake temperatures.
If the DSC indicator lamp comes
on at the same time:
Malfunction in HDC and DSC
system. Refer the problem to your
BMW center.
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When driving with snow chains or
a space-saver spare tire, do not
initialize the system.<
Flat tire
The indicator lamp in the instru-
ment cluster lights up red. This
visual alert is accompanied by
an acoustic warning signal.
1. Carefully reduce speed and come to
a stop. Avoid sudden braking and
steering maneuvers
2. Determine which wheel is damaged
If this cannot be determined, con-
tact your BMW center.<
3. Replace the damaged wheel, refer to
Changing a wheel on page 147.
After replacing the damaged tire, initial-
ize the system.
Vehicles with Run Flat tires:
1. Carefully reduce your speed to under
50 mph / 80 km/h. Avoid strong
braking and steering maneuvers. Do
not exceed a speed of 50 mph /
80 km/h.
Because the sides of Run Flat
tires are reinforced, a drop in infla-
tion pressure usually cannot be
detected from the outside, refer to Run
Flat tires, page 150.<
2. To continue driving, follow the
instructions under Driving with a
damaged tire on page 151.
System malfunction
The indicator lamp in the instru-
ment cluster lights up yellow.
The Flat Tire Monitor is malfunc-
tioning or out of order. Please refer the
problem to your BMW center.
Brake force displayThe brake force display indicates to the
driver of the vehicle behind you how
hard you are braking your vehicle.
The display has two levels:
>Normal braking: the brake lamps
among the rear lamps and the center
brake lamp light up
>Hard braking or use of ABS: the tail
lamps light up with the same bright-
ness as the brake lamps and thereby
intensify the visual effect of the brake
lamps.
Flat Tire Monitor*
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