1999 MERCEDES-BENZ C-CLASS instrument cluster

Brake Assist System (BAS)

Warning !
BAS cannot prevent the natural laws of physics from acting on the vehicle, nor can it increase braking
efficiency beyond that afforded by the condition of the vehicle brakes and tires or the traction afforded. The
BAS cannot prevent accidents, including those resulting from excessive speed in turns, following another
vehicle too closely, or aquaplaning. Only a safe, at tentive, and skillful driver can prevent accidents. The
capabilities of a BAS equipped car must never be explo ited in a reckless or dangerous manner which could
jeopardize the user's safety or the safety of others.

The Brake Assist System is designed to maximize the vehicle's braking capability during emergency braking
maneuvers by having maximum power boost applied to the br akes more quickly in emergency braking conditions
than might otherwise be afforded solely by the driver's braking style. This can help reduce braking distances over
what ordinary driving and braking style might do. The BAS complements the Antilock Brake System (ABS).
To receive the benefit of the system you must apply continuous full braking power during the stopping sequence. Do
not reduce brake pedal pressure.
Once the brake pedal is released, the BAS is deactivat ed The indicator lamps for the ASR and ESP are combined
with the BAS indicator lamp.
The BAS/ASR or BAS/ESP malfunction indicator lamp in the instrument cluster corne on with the electronic key in
steering lock position 2 and should go out with the engine running.
If the BAS/ASR or BAS/ESP malfunction indicator lamp co mes on permanently while the engine is running, a
malfunction has been detected in either system. As a result, it is possible that now only partial engine output will be
available, and pressing the accelerator pedal will require more effort. If the BAS malfunctions. The brake system
functions in the usual manner, but wi thout BAS. If the charging voltage falls be low 10 volts, the malfunction indicator
lamp comes on and the BAS is switched off. When the volt age is above this value again, the malfunction indicator
lamp should go out and the BAS is operational. With t he ABS malfunctioning, the BAS, ASR or ESP are also
switched off. Both malfunction indicator lamps come on with the engine running. Have the BAS, ASR or ESP checked
at your authorized Mercedes-Benz dealer as soon as possible .


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Acceleration Slip Regulation (ASR)
The acceleration slip regulation will engage at all vehicle s peeds, if one or both drive wheels begin to lose traction
and spin in acceleration. While engaged, the yellow warni ng lamp in the speedometer dial flashes. With the
acceleration slip regulation engaged, the brake is applied to the spinning drive wheel until slip is brought under
control. If both drive wheels spin, the brake is applied to both drive wheels and simultaneously, engine torque is
limited, to improve the vehicle's driving stability. As traction on the road surface increases, thus allowing
acceleration without slip, the allowable engine torque also increases again and the brake is no longer applied to
drive wheels.

Important !
If the ASR warning lamp flashes, adapt your spee d and driving to the prevailing road conditions.

Caution !
If the vehicle is towed with the front axle raised (see Towing the vehicle in Index), t he engine must be shut off
(electronic key in steer ing lock position 0 or 1). Othe rwise, the acceleration slip regulation will immediately be
engaged and will apply the rear wheel brakes.

Notes:
The indicator lamp for the ASR is combined with that of the BAS The yellow BAS/ASR malfunction indicator
lamp in the instrument cluster and the yellow ASR warning lamp in the speedometer dial come on with the
electronic key in steering lock position 2. They should go out with the engine running. If the BAS/ASR malfunction
indicator lamp comes on with the engine running, a malfunc tion has been detected in either system. Pressing the
accelerator pedal will require greater effort. Only partial engine output will be available.
If the BAS malfunctions, the brake system functions in the usual manner, but without BAS. Have the BAS or ASR
checked at your authorized Mercedes-Benz dealer as soon as possible. With the ABS malfunctioning, the ASR
is also switched off. Driving the vehicle with varied size tires will cause the wheels to ro tate at different speeds,
therefore the acceleration slip regulation may activate (ye llow ASR warning lamp in speedometer dial comes on).
For this reason, all wheels, including the spare wheel, mu st have the same tire size. When testing the parking
brake on a brake test dynamometer, the engine must be shut off. Otherwise, t he acceleration slip regulation will
immediately be engaged and will apply the rear wheel brakes . In winter operation, the maximum effectiveness of
the acceleration slip regulation is only achieved with Mercedes-Benz recommended M+S rated radialply tires
and/or snow chains.

ASR Control Switch



ASR control switch located in center console To improve
the vehicle's traction when driving with snow chains, or
starting off in deep snow, sand or gravel, press the upper half of the ASR switch. The ASR warning lamp, located
in the speedometer dial, is cont inuously illuminated. With the ASR system switched off, the engine torque
reduction feature is cancelled. Therefore, the enhanced vehicle stability offered by ASR is unavailable. Adapt your
speed and driving to the prevailing road conditions. A por tion of the ASR system remains active, even with the
switch in the OFF position. If one drive wheel loses traction a nd begins to spin, the brake is applied until the wheel
regains sufficient traction. The traction control engages at vehicle speeds up to approximately 24 rnph (40 km/h),
and switches off at 50 mph (80 km/h).
Note:
Avoid spinning of one drive wheel. Doing so may cause seriou s damage to the drive train which is not covered by the
Mercedes-Benz Limited Warranty.
The ASR warning lamp, located in the speedometer dial, star ts to flash at any vehicle speed as soon as the tires
lose traction and the wheels begin to spin. To return to the enhanced vehicle stability offered by ASR: press lower
half of the switch (the ASR warning lamp in the speedometer dial goes out).

Important!
If the ASR warning lamp flashes:
• during take-off, apply as little throttle as possible,
• while driving, ease up on the accelerator.


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Electronic Stability Program (ESP) (optional)

The ESP enhances directional control and reduces driving wheel spin of the vehicle under any driving condition.
Over/understeering of the vehicle is counteracted by applying brakes to the appropriate wheel to create a
counterpointing vehicle movement. The ESP warning lamp, located in the speedometer dial, starts to flash.

Important !
If the ESP warning lamp flashes, adapt your speed and driving to the prevailing road conditions.

Caution !
If the vehicle is towed with the front axle raised (see Towing the vehicle in Index), t he engine must be shut off
(electronic key in steer ing lock position 0 or 1). Otherwise, the el ectronic stability program will immediately be
engaged and will apply the rear wheel brakes.

Notes:
The indicator lamp for the ESP is combined with that of the BAS. The yellow BAS/ESP malfunction indicator lamp
in the instrument cluster and the yellow ESP warning lamp in the speedometer di al come on with the electronic key
in steering lock position 2. They should go out with th e engine running. If the BAS/ESP multifunction indicator lamp
comes on permanently with the engine running, a malfunction has been detected in either system.
Pressing the accelerator pedal will require greater effort. Only partial engine output will be available. If the BAS
malfunctions, the brake system functions in the usual manner, but without BAS. Have the BAS or ESP checked at
your authorized Mercedes-Benz dealer as soon as possible. With the ABS malfunctioning, the ESP is also switched
off. Driving the vehicle with varied size ti res will cause the wheels to rotate at different speeds, therefore the electronic
stability program may activate (yellow ESP warning lamp in speedometer dial comes on).
For this reason, all wheels, including the spare wheel, must have the same tire size. When testing the parking brake
on a brake test dynamometer, the engine must be shut off. Otherwise, t he electronic stability program will
immediately
be engaged and will apply the rear wheel brakes. In winter operation, the maximum effectiveness of the electronic
stability program is only achieved with Mercedes-Benz reco mmended M+S rated radial-ply tires and/or snow chains.

ESP Control Switch



ESP control switch located on center co
nsole To improve the vehicle's traction when driving with snow chains, or
starting off in deep snow, sand or gravel, press the upper half of the ESP switch. The ESP warning lamp, located in
the speedometer dial, is continuously illuminated. With the ESP system switched off, the engine torque reduction
feature is cancelled. Therefore, the enhanced vehicle stability offered by ESP is unavailable. Adapt your speed and
driving to the prevailing road conditio ns. A portion of the ESP system remains ac tive, even with the switch in the OFF
position. If one drive wheel loses traction and begins to spin , the brake is applied until the wheel regains sufficient
traction. The traction control engages at vehicle speeds up to approximately 24 mph (40 km/h), and switches off at 50
mph (80 km/h).

Note:
Avoid spinning of one drive wheel. Doing so may cause seriou s damage to the drive train which is not covered by the
Mercedes-Benz Limited Warranty. The ESP warning lamp, located in the speedome ter dial, starts to flash at any
vehicle speed as soon as the tires lose traction and the wheels begin to spin. To return to the enhanced vehicle
stability
offered by ESP: press lower half of the switch (the ESP warning lamp in the speedometer dial goes out).

Important !
If the ESP warning lamp flashes:
• during take-off, apply as little throttle as possible,
• while driving, ease up on the accelerator.


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Emission Control
Certain systems of the engine serve to keep the toxic components of the exhaust gases within
permissible limits required by law. These syst ems, of course, will function properly only when
maintained strictly according to factory spec ifications. Any adjustments on the engine should,
therefore, be carried out only by qualified Merc edes-Benz authorized dealer technicians. Engine
adjustments should not be altered in any way. Moreover, the specified service jobs must be carried
out regularly according to Mercedes-Benz servicing requirements. For details refer to the Service
Booklet.

Warning !
Inhalation of exhaust gas is hazardous to your health. All exhaust gas contains carbon
monoxide, and inhaling it can cause unconsciousness and lead to death.
Do not run the engine in confined areas (such as a garage) which are not properly ventilated.
If you think that exhaust gas fumes are entering the vehicle while driving, have the cause
determined and corrected immediately. If you must drive under these conditions, drive only
with at least one window fully open.


On-Board Diagnostic System
The Sequential Multiport Fuel Injection (SFI) c ontrol module monitors emission control components
that either provide input signals to or receive output signals from the control module. Malfunctions
resulting from interruptions or failure of any of these components are indicated by the "CHECK
ENGINE" malfunction indicator lamp in the instrument cluster and are simultaneously stored in the
diagnostic module. If the "CHECK ENGINE" malfunc tion indicator lamp comes on, have the system
checked at your authorized Mercedes-Benz deal er as soon as possible. The control module
switches off the "CHECK ENGINE" indicator lamp if the condition, causing the lamp to come on, no
longer exists. An on-board diagnostic connector is located in the passenger compartment near to the
parking brake pedal, allowing the accurate identificat ion of system malfunctions through the readout
of diagnostic trouble codes.


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Instrument Cluster
Use a gentle dish-washing detergent or mild detergent for delicate fabrics as a washing solution.
Wipe with a cloth moistened in lukewarm solution. Do not use scouring agents.


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