Check engine MERCEDES-BENZ C240 2002 W203 Owner's Guide

288 Malfunction and indicator lamps
Te ch n i c a l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car care Index
Brake warning lamp
Except Canada
Canada only
When the brake warning lamp and message appear
while the engine is running, this means:
•there is insufficient brake fluid in the reservoir
(engine running and parking brake released), or
•the parking brake is set (engine running).Note:
If you find that the minimum mark on the brake fluid
reservoir is reached, have the brake system checked for
brake pad thickness and leaks.
Wa r n i n g !
Driving with the brake warning lamp illuminated
can result in an accident. Have your brake system
checked immediately if the brake warning lamp
stays on. Don’t add brake fluid before checking the
brake system. Overfilling the brake fluid reservoir
can result in spilling brake fluid on hot engine
parts and the brake fluid catching fire. You can be
seriously burned.
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289 Malfunction and indicator lamps
Te ch n i c a l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car care Index Supplemental restraint system (SRS) indicator lamp
When turning the electronic key in starter
switch to position 1 the indicator lamp “SRS”
in the instrument cluster comes on. If no
fault is detected, the lamp will go out after
approximately 4 seconds.
When turning the electronic key in starter switch to
position 2 the indicator lamp “SRS” in the instrument
cluster comes on. If no fault is detected, the lamp will go
out when the engine is running.
The operational readiness of the airbag system is
verified by the indicator lamp “SRS” in the instrument
cluster when turning the electronic key in starter switch
to position 1 or 2.After the lamp goes out, the system continues to
monitor the components and circuitry of the airbag
system and will indicate a malfunction by coming on
again.
See page 73 for notes on airbags, see page 71 for belt
tensioners and page 63 for infant and child seat
restraint.
Wa r n i n g !
In the event a malfunction of the “SRS” is indicated
as outlined above, the “SRS” may not be
operational. For your safety, we strongly
recommend that you visit an authorized
Mercedes-Benz Center immediately to have the
system checked; otherwise the “SRS” may not be
activated when needed in an accident, which could
result in serious or fatal injury, or it might deploy
unexpectedly and unnecessarily which could also
result in injury.
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291 Malfunction and indicator lamps
Te ch n i c a l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car care Index ABS malfunction indicator lamp
The ABS malfunction indicator lamp in the
instrument cluster comes on with the
electronic key in starter switch position 2
and should go out with the engine running.
When the ABS malfunction indicator lamp symbol and
warning in the instrument cluster remains illuminated
while the engine is running, it indicates that the ABS
has detected a malfunction and has switched off. In this
case, the brake system functions in the usual manner,
but without antilock assistance.
A malfunctioning ABS control unit can possibly affect
the operation of other systems (e.g. Navigation,
Automatic transmission). Be guided accordingly with
respect to the use of those systems and have the system
checked at your authorized Mercedes-Benz Center as
soon as possible.With the ABS malfunctioning, the BAS and ESP are also
switched off. The malfunction indicator lamps and
malfunction messages in the multifunction display
come on with the engine running.
If the charging voltage falls below 10 volts, the
malfunction indicator lamp comes on and the ABS is
switched of f. When the voltage is above this value again,
the malfunction indicator lamp should go out and the
ABS is operational.
Have the system checked at your authorized
Mercedes-Benz Center as soon as possible.
See page 276 for notes on antilock brake system (ABS).
ABS
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298 Malfunction and warning messages
Te ch n i c a l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car care Index
BRAKE PAD WEAR
* C = Category, see page 293When this message appears during braking, it indicates
that the brake pads are worn down.
Have the brake system checked at your authorized
Mercedes-Benz Center as soon as possible.BRAKE FLUID
* C = Category, see page 293 Line 1 Line 2 C*
BRAKE PAD WEAR VISIT WORKSHOP! 2Line 1 Line 2 C*
BRAKE FLUID VISIT WORKSHOP! 2Wa r n i n g !
Driving with this message displayed can result in
an accident. Have your brake system checked
immediately. Don’t add brake f luid before checking
the brake system. Overfilling the brake fluid
reservoir can result in spilling brake fluid on hot
engine parts and the brake fluid catching fire. You
can be seriously burned.
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301 Malfunction and warning messages
Te ch n i c a l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car care Index COOLANT (coolant level)
* C = Category, see page 293When this message appears while driving, the coolant
level has dropped below the required level. If no leaks
are noticeable and the engine temperature does not
increase, continue to drive to the nearest service station
and have coolant added to the coolant system.The low engine coolant level warning should not be
ignored. Extended driving with the symbol displayed
may cause serious engine damage not covered by the
Mercedes-Benz Limited Warranty.
In cases of major or frequent minor coolant loss, have
the cooling system checked at your authorized
Mercedes-Benz Center as soon as possible.
Note:
Do not drive without coolant in the cooling system. The
engine will overheat causing major engine damage.
Monitor the coolant temperature gauge while driving,
see page 137.
See page 323 for instructions on topping up the coolant.Line 1 Line 2 C*
COOLANT CHECK LEVEL! 2
Wa r n i n g !
Do not spill antifreeze on hot engine parts.
Antifreeze contains ethylene glycol which may
burn if it comes into contact with hot engine parts.
You can be seriously burned.
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303 Malfunction and warning messages
Te ch n i c a l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car care Index ENGINE OIL LEVEL
* C = Category, see page 293.
1 The engine oil level must be checked immediately. See Engine oil
level indicator on page 141.
2 There is no oil in the engine. There is a danger of engine damage.3 There is a risk of damaging the engine or catalytic converter. The
engine oil level must be checked immediately. See Engine oil level
indicator on page 141.
4 The engine oil level has dropped to a critical level.
Check the engine oil level immediately. See Engine oil level
ind icator on page 141 and check the en gine fo r visibl e leakage (los s
of oil).
It may be that there is water in the engine oil. Have the engine oil
checked.
5 The measuring system is malfunctioning.
When the “ENGINE OIL LEVEL – CHECK LEVEL!”
message appears while the engine is running and at
operating temperature, the engine oil level has dropped
to approximately the minimum mark on the dipstick.
When this occurs, the warning will first come on
intermittently and then stay on if the oil level drops
further.
If no oil leaks are noted, continue to drive to the nearest
service station where the engine oil should be topped to
the “full” mark on the dipstick with an approved oil.
The engine oil level warnings should not be ignored.
Extended driving with the symbol displayed could
result in serious engine damage that is not covered by
the Mercedes-Benz Limited Warranty.
Line 1 Line 2 C*
ENGINE OIL LEVEL CHECK LEVEL!
1
2
ENGINE OIL LEVEL STOP, ENGINE OFF!
2
1
ENGINE OIL LEVEL REDUCE OIL LEVEL1
3
2
ENGINE OIL VISIT WORKSHOP!
4
2
ENGINE OIL LEVEL VISIT WORKSHOP!
5
2
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309 Malfunction and warning messages
Te ch n i c a l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car care Index WA S H E R F L U I D
* C = Category, see page 293.
When this message appears while the engine is
running, the level of the reservoir has dropped to
approximately
1/3 of the total volume. The reservoir
should be refilled with the prescribed mixture of MB
Windshield washer concentrate and water or the
concentrate and commercially available premixed
windshield washer solvent / antifreeze, depending on
ambient temperature, at the next opportunity. The
reservoir for the windshield and headlamp washer
systems is located in the engine compartment.
See windshield and headlamp washer system on
page 323 for instructions on topping up the washer
fluid.
Line 1 Line 2 C*
WASHER FLUID CHECK LEVEL! 3
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321 Engine compartment
Te ch n i c a l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hintsCar care Index Adding engine oil
1Oil filler cap
2Plug of dipstick guide tube
The engine oil level can only be checked via the
multifunction display in the instrument cluster.
To check the engine oil level, park vehicle on level
ground, with engine at normal operational temperature.
Check engine oil level approximately 5 minutes after
stopping the engine, allowing for the oil to return to the
oil pan.Unscrew the oil filler cap and add oil carefully if you
need to top up the oil. Follow the message appearing on
the engine oil level indicator display (page 141) as to
quantity to be added. Re-install oil filler cap.
Do not overfill the engine.
Excessive oil must be drained
or siphoned. It could cause damage to engine and
catalytic converter not covered by the Mercedes-Benz
Limited Warranty.
See malfunction and warning messages on page 293 if
an engine oil level display appears on the multifunction
indicator when the engine is running.
Notes:
See page 141 for engine oil level indicator display.
The dipstick tube allows for draining of oil by using a
suction device.
1
P 01.00-2219-26
2
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322 Engine compartment
Te ch n i c a l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hintsCar care Index
Automatic transmission fluid level
The transmission has a permanent fill of automatic
transmission fluid.
Regular automatic transmission fluid level checks and
changes are not required. For this reason the dipstick is
omitted.
If you notice fluid leaks or gear shifting malfunctions,
have your authorized Mercedes-Benz Center check the
transmission fluid level.Coolant level
1Coolant expansion tank
To check the coolant level, the vehicle must be parked
on level ground and the engine stopped.
Check coolant level only when coolant is cold.
The coolant level should reach the black top part of the
reservoir.
See page 385 for antifreeze / anticorrosion mixture.
P 20.30-2133-26
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342 Battery
Te ch n i c a l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hintsCar care Index
warm tires only if pressure has dropped below the
pressure listed in the table and the respective operating
conditions are taken into consideration.
An underinflated tire due to a slow leak (e.g. due to a
nail in the tire) may cause damage such as tread
separation, bulging etc. Regular tire pressure checks
(including the spare tire) at intervals of no more than
14 days are therefore essential.
If a tire constantly loses air, it should be inspected for
damage.
The spare tire should be checked periodically for
condition and inflation. Spare tire will age and become
worn over time even if never used, and thus should be
inspected and replaced when necessary.Battery
Important!
Battery replacement information:
The maintenance-free battery is located in the engine
compartment on the right hand side.
The service life of the battery is dependent on its
condition of charge. The battery should always be kept
sufficiently charged, in order to last an optimum length
of time.
Wa r n i n g !
Do not overinflate tires. Overinflating tires can
result in sudden deflation (blowout) because they
are more likely to become punctured or damaged
by road debris, potholes etc. Follow recommended
inflation pressures.Do not overload the tires by exceeding the specified
vehicle capacity weight as indicated by the label on
the driver’s door latch post). Overloading the tires
can overheat them, possibly causing a blowout.
Wa r n i n g !
Failure to follow these instructions can result in
severe injury or death.Never lean over batteries while connecting, you
might get injured.Battery fluid contains sulfuric acid. Do not allow
this fluid to come in contact with eyes, skin or
clot hin g. In cas e i t d oes , i mm ed ia tely f lus h a f fected
area with water and seek medical help if necessary.A battery will also produce hydrogen gas, which is
flammable and explosive. Keep flames or sparks
away from battery, avoid improper connection of
jumper cables, smoking etc.
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