2003 MERCEDES-BENZ SL500 brakes

234 OperationTires and wheels
Tires and wheelsSee your authorized Mercedes-Benz Cen-
ter for information on tested and recom-
mended rims and tires for summer and
winter operation. They can also offer ad-
vice concerning tire service and purchase.
Retread tires are not tested or recom-
mended by Mercedes-Benz, since previous
damage cannot always be recognized on
retreads. Mercedes-Benz can therefore
not assure the operating safety of the vehi-
cle when such tires are used.
See your authorized Mercedes-Benz Cen-
ter for information on tested and recom-
mended rims and tires for summer and
winter operation.
Important guidelines

Only use sets of tires and rims of the
same type and make.


Tires must be of the correct size for the
rim.


Break in new tires for approximately
60 miles (100 km) at moderate
speeds.


Regularly check the tires and rims for
damage.


If vehicle is heavily loaded, check tire
pressure and correct as required.


Do not allow your tires to wear down
too far. Adhesion properties on wet
roads are sharply reduced at tread
depths under
1/8in (3 mm).


When replacing individual tires, you
should mount new tires on the front
wheels first (on vehicles with
same-sized wheels all around).
Warning!
G
Replace rims or tires with the same designa-
tion, manufacturer and type as shown on the
original part. See your authorized
Mercedes-Benz Center for further informa-
tion. If incorrectly sized rims and tires are
mounted:

The wheel brakes or suspension compo-
nents can be damaged.


The correct operating clearance of the
wheels and the tires is no longer guaran-
teed.
Warning!
G
Worn, old tires can cause accidents. If the
tire tread is badly worn, or if the tires have
sustained damage, replace them.
When replacing rims, only use genuine
Mercedes-Benz wheel bolts specified for the
particular rim type. Failure to do so can re-
sult in the bolts loosening and may lead to
an accident.

236 OperationTires and wheelsRegularly check your tire pressure at inter-
vals of no more than 14 days.
Tire pressure changes by approximately
1.5 psi (0.1 bar) per 18°F (10°C) of air
temperature change. Keep this in mind
when checking tire pressure where the
temperature is different from the outside
temperature.
The tire temperature and with it the tire
pressure is increased also while driving,
depending on the driving speed and the
tire load.
Checking tire pressure electronically*
The tire inflation pressure monitor only
functions on wheels that are equipped with
the proper electronic sensors. It monitors
the tire inflation pressure, as selected by
the driver, in all four tires. A warning is is-
sued to alert you to a decrease in pressure
in one or more of the tires.Tire pressure inquiries are made using the
multifunction display (
page 110). The
present inflation pressures are displayed
only after a few minutes travel time.
You can select the unit of measure used for
the tire inflation pressure by changing the
setting in the control system (
page 129).

Switch on ignition.

Press
k
button until the current in-
flation pressures for each tire appear in
the tachometer display field.
iPossible differences between the read-
ings of a tire pressure gauge of an air
hose, e.g. gas station equipment, and
the vehicle’s control system can occur.
The readings issued by the control sys-
tem are more precise.
Warning!
G
The tire inflation pressure monitor does not
indicate a warning for wrongly selected in-
flation pressures. Always adjust tire inflation
pressure according to the label on the fuel
filler flap.
The tire inflation pressure monitor is not
able to issue a warning due to a sudden loss
of pressure (e.g. tire puncture caused by a
foreign object). In the event of a sudden loss
of pressure, bring the vehicle to a halt by
carefully applying the brakes and avoiding
abrupt steering maneuvers.

251 Practical hints
What to do if …
Problem
Possible cause
Suggested solution
-
The yellow ABS malfunction indi-
cator lamp comes on while driv-
ing.
The ABS has detected a malfunction and has
switched off. The BAS and ESP are also
switched off (see messages in display).
The SBC brake system is still functioning nor-
mally but without ABS available.
If the ABS control unit is malfunctioning, oth-
er systems such as Parktronic*, Distronic*,
or the automatic transmission may also be
malfunctioning.

Continue driving with added caution.
Wheels may lock during hard braking,
reducing steering capability.

Have the system checked at an autho-
rized Mercedes-Benz Center as soon
as possible.
Failure to follow these instructions in-
creases the risk of an accident.

Read and observe messages in the
display (
page 257).
E
The red DTR indicator lamp lights
up while driving.
You are too close to the vehicle in front of you
to maintain selected speed.

Apply the brakes immediately to in-
crease the following distance.
E
The red DTR indicator lamp
comes on while driving and you
hear a warning sound.


You are gaining too rapidly on the vehicle
ahead of you.


The distance warning system has recog-
nized a stationary obstacle on your prob-
able line of travel.

Apply the brakes immediately.

Carefully observe the traffic situation.
You may need to brake or maneuver
to avoid hitting an obstacle.
E
The white DTR indicator lamp
lights up while driving.
The Distronic* distance sensor has recog-
nized a vehicle in front of you.

267 Practical hints
What to do if …
Warning!
G
Driving while these messages are displayed
can result in an accident. Have your brake
system checked immediately.
If there is a malfunction in the SBC brake
system, we recommend that the vehicle be
transported with all wheels off the ground
using flatbed or appropriate wheel lift/dolly
equipment. A tow bar must be used if cir-
cumstances do not permit the use of the
recommended towing methods and the ve-
hicle requires towing with all four wheels on
the ground. Towing the vehicle with all four
wheels on the ground is only permissible for
distances up to 30 miles (50 km) and at a
speed not to exceed 30 mph (50 km/h). For
more information, refer to "Towing the
vehicle"(
page 325).
If the SBC brake system enters its emergen-
cy operation mode, the driver must apply
significantly greater brake pedal pressure
and depress the pedal much further than
normal to obtain braking effect.
If necessary, apply full pressure to the brake
pedal. Brakes are only applied to the front
wheels. Stopping distance is increased!
Low brake fluid in the reservoir may cause
the braking system to fail!
If necessary, apply full pressure to the brake
pedal. Brakes are only applied to the front
wheels. Stopping distance is increased!
Low brake fluid in the reservoir may cause
the braking system to fail!
Don’t add brake fluid before checking the
brake system. Overfilling the brake fluid res-
ervoir can result in spilling brake fluid on hot
engine parts and the brake fluid catching
fire. You can be seriously burned.

268 Practical hintsWhat to do if …Left display
Right display
Possible cause
Possible solution
Except Canada:;Canada only:3
Service brake
Visit workshop!
There are malfunctions, but the SBC
brake system is operating normally.

Visit an authorized Mercedes-Benz Center as
soon as possible.
Incr.
braking distance
Start engine!
The battery has insufficient voltage
and cannot supply sufficient power
to the SBC brake system.

Start the engine.
The message disappears when sufficient
voltage is available.
Brakes overheated!
Drive carefully!
The brake system is overheated due
to an excessive load on the brakes.

Relieve the load on the brake system.

Drive more smoothly and think ahead to
avoid unnecessary braking.

When driving down steep grades, shift into a
lower gear to use the engine’s braking power
(page 139).

Cautiously continue driving so that the air
stream will cool down the brakes.

320 Practical hintsBatteries
Disconnecting the batteriesDisconnecting the battery for electrical
consumers

Unhook the luggage cover in the trunk.

Remove the trunk floor.
The battery for electrical consumers is
located in the right hand area of the
trunk (
page 289).

Use the 10 mm open-end wrench from
the vehicle tool kit to disconnect the
battery negative lead.

Remove the cover from the positive ter-
minal.

Disconnect the battery positive lead.
Disconnecting the starter battery

Use the 10 mm open-end wrench from
the vehicle tool kit to disconnect the
battery negative lead.

Remove the cover from the positive ter-
minal.

Disconnect the battery positive lead.
Warning!
G
The brake system requires electrical power
to operate.
A malfunction in the vehicle’s power supply
or electrical system may impair brake sys-
tem operation and switch it into its
limp-home (emergency operation) mode.
The same applies if battery is disconnected.
To brake, the driver must then apply signifi-
cantly greater brake pedal pressure and de-
press the pedal much further to obtain the
expected braking effect. If necessary, apply
full pressure to the brake pedal. Brakes are
only applied to the front wheels. Stopping
distance is increased! Adjust your driving
style accordingly. SBC brake system
(page 72).
Warning!
G
With a disconnected battery

y o u w i l l n o l o n g e r b e a b l e t o t u r n t h e k e y
in the starter switch and pressing the
KEYLESS-GO
* start/stop button (if so
equipped) on the selector lever will have
no effect


the selector lever will remain locked in
positionP!To avoid damage to electrical compo-
nents, always disconnect the battery
for electrical consumers (in trunk) first.
This applies even if you only wish to
charge the starter battery. Otherwise
the electronics of the vehicle can be
damaged.

325 Practical hints
Towing the vehicle
Towing the vehicle
Mercedes-Benz recommends that the vehi-
cle be transported with all wheels off the
ground using flatbed or appropriate wheel
lift/dolly equipment.When circumstances do not permit the
recommended towing methods, the vehi-
cle may be towed with all wheels on the
ground or front wheels raised only so far as
necessary to have the vehicle moved to a
safe location where the recommended
towing methods can be employed.
!Use flatbed or wheel lift/dolly equip-
ment with key in starter switch turned
to position0.
Do not tow with sling-type equipment.
Towing with sling-type equipment over
bumpy roads will damage radiator and
supports.
To prevent damage during transport,
do not tie down vehicle by its chassis or
suspension parts.
Switch off the tow-away alarm and the
automatic central locking.
!If the vehicle is towed with the front
axle raised, the engine must be shut off
(key in starter switch position0 or1).
Otherwise, the ESP will immediately be
engaged and will apply the rear wheel
brakes.
When towing the vehicle with all wheels
on the ground, the selector lever must
be in positionN and the key must be in
starter switch position2.
When towing the vehicle with all wheels
on the ground or the front axle raised,
the vehicle may be towed only for dis-
tances up to 30 miles (50 km) and at a
speed not to exceed 30 mph (50
km/h).
!To be certain to avoid a possibility of
damage to the transmission, however,
we recommend the drive shaft be dis-
connected at the rear axle drive flange
for any towing beyond a short tow to a
nearby garage.

326 Practical hintsTowing the vehicleWarning!
G
If circumstances require towing the vehicle
with all wheels on the ground, always tow
with a tow bar if:

the engine will not run


there is a malfunction in the SBC brake
system


there is a malfunction in the power sup-
ply or in the vehicle’s electrical system
as that will be necessary to adequately con-
trol the towed vehicle.
Prior to towing the vehicle with all wheels on
the ground, make certain that the key is in
starter switch position2.
If the key is left in the starter switch
position0 for an extended period of time, it
can no longer be turned in the switch. In this
case, the steering is locked. To unlock, re-
move key from starter switch and reinsert.
iTo signal turns while being towed with
the hazard warning flasher in use, turn
key in starter switch to position2 and
activate the combination switch for the
left or right turn signal in the usual
manner – only the selected turn signal
will operate.
Upon canceling the turn signal, the haz-
ard warning flasher will operate again.
Warning!
G
The brake system requires electrical power
to operate.
A malfunction in the vehicle’s power supply
or electrical system may impair brake sys-
tem operation and switch it into its
limp-home (emergency operation) mode. To
brake, the driver must then apply signifi-
cantly greater brake pedal pressure and de-
press the pedal much further to obtain the
expected braking effect. If necessary, apply
full pressure to the brake pedal. Brakes are
only applied to the front wheels. Stopping
distance is increased! Adapt your driving
style accordingly. SBC brake system
(page 72).
With the engine not running, there is no
power assistance for the steering system. In
this case, it is important to keep in mind that
a considerably higher degree of effort is nec-
essary to steer the vehicle. Adapt your driv-
ing accordingly.