check engine light MERCEDES-BENZ R320CDI 2007 R171 Owner's Guide

455 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
•Coolant level
Stop car, switch engine
offThe coolant is too hot.
Among other possible causes
(the cooling fan could be
malfunctioning), the poly-V-belt
could be broken.Stop the vehicle in a safe location or
as soon as it is safe to do so.
Turn off the engine.
Apply the parking brake (page 66).
Check the poly-V-belt.
If it is broken:
Do not continue to drive. Otherwise
the engine will overheat due to an
inoperative water pump which may
result in damage to the engine.
Contact an authorized
Mercedes-Benz Light Truck Center.
If it is intact:
Wait for the message to disappear
before restarting the engine.
Doing otherwise could result in seri-
ous engine damage that is not
covered by the Mercedes-Benz
Limited Warranty.
(Continued on next page)

457 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
B Top up coolant
See Oper. ManualThe coolant level is too low.Add coolant (page 370).
If you have to add coolant frequently,
have the cooling system checked by an
authorized Mercedes-Benz Light Truck
Center.
Warning!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 could be seriously burned.
!Do not ignore the low engine coolant level
warning. Extended driving with the message and
symbol displayed may cause serious engine
damage not covered by the Mercedes-Benz
Limited Warranty.
Do not drive without sufficient amount of coolant
in the cooling system. The engine will overheat,
causing major engine damage.

458 Practical hints
What to do if …
When the message Add 1 qt. engine oil
when next refueling
(Canada: 1 liter)
appears while the engine is running and at
operating temperature, the engine oil level
has dropped to approximately the mini-
mum level.
When this occurs, the warning will first
come on intermittently and then stay on if
the oil level drops further.Visually check for oil leaks. If no obvious oil
leaks are noted, drive to the nearest
service station where the engine oil should
be topped to the required level with an
approved oil specified in the Factory
Approved Service Products pamphlet.
Display symbolDisplay messagePossible cause/consequencePossible solution
NCheck eng. oil level
at next refuelingThe engine oil level is too low.Check the engine oil level (page 366).
USA only:
Add 1 qt. engine oil
at next refueling
Canada only:
Add 1 liter engine oil
at next refueling
The engine oil level is too low.Add engine oil (page 369) and check
the engine oil level (
page 366).
Engine oil level
cannot be measuredThe measuring system is
malfunctioning.Have the measuring system checked by
an authorized Mercedes-Benz Light Truck
Center.

507 Practical hints
Battery
!The battery is a valve-regulated lead acid
(VRLA) battery, also referred to as “fleece”
battery. Such batteries do not require topping-up
of the electrolyte level. VRLA batteries therefore
do not have cell caps and the battery cover is
non-removable. Do not attempt to open the
battery as otherwise the battery will be dam-
aged.
Even though VRLA batteries do not require
topping-up of the electrolyte level and cannot be
opened to check the electrolyte level, the
battery condition must be checked periodically
by performing a battery conductance test. Refer
to Maintenance Booklet for battery condition
testing intervals.
As with any other battery, the battery may
discharge if the vehicle is not operated for an
extended period of time. You can connect a
battery maintenance charge unit tested and
approved for use on your vehicle model or dis-
connected the battery to prevent battery dis-
charge. Contact an authorized Mercedes-Benz
Light Truck Center for more information.!The factory-equipped VRLA battery is
leak-proofed. Only use a battery as replacement
that has the same security features and is of
identical size, voltage, and capacity as the
factory-equipped battery.
The battery, the battery ventilation and the later-
al plug must always be securely installed when
the vehicle is in operation.
Warning!G
Jump starting must only be done using the
jump-start contacts located in the engine
compartment (
page 514).
Warning!G
Failure to follow these instructions can re-
sult in severe injury or death.
Observe all safety instructions and precau-
tions when handling automotive batteries
(
page 506).
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 clothing. In case it does, immediately
flush affected 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.

508 Practical hints
Battery
Disconnecting, removing, reinstalling
and reconnecting the battery
Step 1 (Disconnecting)
Set the automatic transmission to
positionP (
page 199).
Firmly depress the parking brake
(
page 66).
Turn off the engine (page 67).
Leave the ignition switched on
(
page 39).
!Never loosen or detach battery terminal
clamps while the engine is running or the
SmartKey is in the starter switch. Otherwise the
alternator and other electronic components
could be severely damaged.
Have the battery checked regularly by an autho-
rized Mercedes-Benz Light Truck Center.
Contact your authorized Mercedes-Benz Light
Truck Center for further information.
Warning!G
Do not place metal objects on the battery as
this could result in a short circuit.
Use leak-proof battery only to avoid the risk
of acid burns in the event of an accident.
Warning!G
Disconnecting, removing, reinstalling and
reconnecting the battery is a complicated
and technically demanding procedure that
a l s o r e q u i r e s s a f e t y p r e c a u t i o n s t o a v o i d t h e
risk of injury. We strongly recommend that it
be performed by a qualified technician or an
authorized Mercedes-Benz Light Truck
Center only. Please read the instructions
fully before beginning operation and only
undertake it if you feel fully capable of
performing all of the tasks involved as
described in these instructions. Observe all
safety instructions and precautions when
handling automotive batteries
(
page 506). Performing the tasks involved
incorrectly can cause damage to the vehicle
and impair the operating safety of the
vehicle, and/or cause severe injury to you
or others.
iWith a disconnected battery you will no long-
er be able to turn the SmartKey in the starter
switch and pressing the KEYLESS-GO*
start/stop button will have no effect.
iIf your battery is discharged, the vehicle
must be jump started (
page 514) using the
jump start contacts in the engine compartment,
or an accessory battery charge unit* approved
by Mercedes-Benz must be connected using the
jump start contacts in the engine compartment
(see separate instructions for the accessory
battery charge unit*) before any of the following
steps can be performed. If the battery cannot be
jumped or charged, please contact an autho-
rized Mercedes-Benz Light Truck Center.

514 Practical hints
Jump starting
If the battery is discharged, the engine can
be started with jumper cables and the bat-
tery of another vehicle. Observe the follow-
ing:

Jump starting should only be performed
using the jump-start contacts in the en-
gine compartment (
page 515).

Jump starting should only be performed
when the engine and catalytic
converter
1 are cold.

Do not start the engine if the battery is
frozen. Let the battery thaw out first.

Only jump start from batteries with the
same voltage rating (12 V). Jump start-
ing with a more powerful battery could
damage the vehicle’s electrical system,
which will not be covered by the
Mercedes-Benz Limited Warranty.

Use only jumper cables with sufficient
cross-section and insulated terminal
clamps.

Always make sure the jumper cables
are not on or near pulleys, fans or other
parts that move when the engine is
started or running.
Warning!G
Failure to follow these directions will cause
damage to the electronic components, and
can lead to a battery explosion and severe
injury or death.
Never lean over batteries while connecting
or jump starting, you might get injured.
Battery fluid contains sulfuric acid. Do not
allow this fluid to come in contact with eyes,
skin or clothing. In case it does, immediately
flush affected area with water, and seek
medical help if necessary.
A battery will also produce hydrogen gas,
which is flammable and very explosive. Keep
flames or sparks away from battery, avoid
improper connection of jumper cables,
smoking, etc.
Attempting to jump start a frozen battery
can result in it exploding, causing personal
injury.
Read all instructions before proceeding.
1Vehicles with gasoline engine only.
!Do not tow-start the vehicle.
!Avoid repeated and lengthy starting
attempts.
Do not attempt to start the engine using a
battery quick charge unit.
If the engine does not run after several unsuc-
cessful starting attempts, have it checked at the
nearest authorized Mercedes-Benz Light Truck
Center.
Excessive unburned fuel generated by repeated
failed starting attempts may damage the cata-
lytic converter
1.
Make sure the jumper cables do not have loose
or missing insulation.
Make sure the cable clamps do not touch any
other metal part while the other end is still at-
tached to a battery.

516 Practical hints
Jump starting
Connect positive terminals2 and 4
with the jumper cable. Clamp cable to
charged battery 4 first.
Start engine of the vehicle with the
charged battery and run at idle speed.
Connect negative terminals1 and 3
of the batteries with the jumper cable.
Clamp cable to charged battery 3
first.
Start the engine of the disabled vehi-
cle.You can now turn on the electrical con-
sumers. Do not switch on the headlamps
under any circumstances.
Remove the jumper cables first from
negative terminals1 and 3 and then
from the positive terminals2 and 4.
You can now switch on the headlamps.
Have the battery checked at the
nearest authorized Mercedes-Benz
Light Truck Center.
!Never invert the terminal connections!


545 Technical data
Fuels, coolants, lubricants, etc.
Anticorrosion/antifreeze
Your vehicle contains a number of
aluminum parts. The use of aluminum
components in motor vehicle engines ne-
cessitates that anticorrosion/antifreeze
coolant used in such engines be
specifically formulated to protect the aluminum parts. (Failure to use such anti-
corrosion/antifreeze coolant will result in
a significantly shortened service life.)
Therefore, the following product is strongly
recommended for use in your vehicle:
Mercedes-Benz 325.0 anticorrosion/anti-
freeze agent.Before the start of the winter season (or
once a year in hot southern regions), you
should have the anticorrosion/antifreeze
concentration checked. The coolant is also
regularly checked each time you bring your
vehicle to an authorized Mercedes-Benz
Light Truck Center for service.
Anticorrosion/antifreeze quantity
Approx. freeze protection
Model–35°F (–37°C)–49°F (–45°C)
R 320 CDI5.0 US qt (4.75 l)5.5 US qt (5.2 l)
R3505.0 US qt (4.75 l)5.5 US qt (5.2 l)
R5005.6 US qt (5.25 l)6.1 US qt (5.8 l)
R63 AMG6.1US qt (5.75l)6.8 US qt (6.4 l)

548 Index
Automatic climate control (3-zone)* 232
Air conditioning, Cooling 243
Air conditioning refrigerant 540
Air distribution 238
Air recirculation mode 240
Air vents, Front 232, 238
Air vents, Rear 245, 249
Air volume 239
Control panel, Front 234
Control panel, Rear 245
Deactivating system 236
Defogging 240
Defrosting 239
Maximum cooling, MAX COOL 240
Rear passenger compartment 245
Residual heat utilization (REST) 244
Automatic headlamp mode 147
Automatic lighting control, Interior
lighting 154
Automatic locking when driving 130
Automatic shift program 206Automatic transmission 197
Accelerator position 203
Automatic shift program 206
Emergency operation
(limp-home mode) 211
Gear ranges 205
Gear selector lever 54, 197
Gear shifting malfunctions 211
Hill start assist system 204
Kickdown 203
Kickdown, manual shift program
(R 63 AMG only) 211
Manual shift program
(R 63 AMG only) 209
Program mode selector switch 206
Shifting procedure 200
Starting the engine 54
Steering wheel gearshift control 207
Transmission fluid level 370
Transmission positions 201
Automatic transmission fluid see ATF
AUX-socket 311B
Backrest
Seat 44
Seat, Lumbar support 136
Seat, Multicontour* 136
Backup lamps
Messages in the multifunction
display 463–468
Replacing bulbs 484
Bar 401
BAS 102
Lamps in instrument cluster 420
Messages in the multifunction
display 435
Batteries, SmartKey
Check lamp 112, 116
Checking battery condition 115, 120
Battery, Vehicle 506
Charging 513
Disconnecting and connecting 508
Jump starting 514
Removing and installing 508
Bead 401

549 Index
Beverage holder see Cup holder
Bleeding the fuel system
(diesel engine) 505
Bolts, Spare wheel 500
Bottle opener 317
Brake Assist System see BAS
Brake fluid 541
Checking 362
Messages in the multifunction
display 454
Brake lamp
Cleaning lenses 413
Messages in the multifunction
display 463–468
Replacing bulbs 484
Brake pads 348
Messages in the multifunction
display 452
Brakes 348
High-performance brake system
(AMG vehicles only) 350
Warning lamp 421
Break-in the vehicle 346
Bulbs, replacing see Replacing bulbsC
California retail buyers and lessees,
Important notice for 11
Call priority, Tele Aid* 336
Can holder see Cup holder
Capacities and recommended
fuel/lubricants 538
Card holder 32, 317
Cargo compartment
Tie-down rings 299
Cargo compartment cover blind* 306
Cargo tie-down rings 299
Carpets, Cleaning 417
Catalytic converter
(gasoline engine) 357
CD changer* 172, 311
CD player 172
Center console 31
Central locking 189
Automatic 130
Locking/unlocking from the
inside 130
Central locking switch 130Certification label 526, 527
CHECK ENGINE malfunction
indicator lamp 423, 424
Checking tire pressure electronically
Advanced Tire Pressure Monitoring
System (Advanced TPMS)*,
(Canada only) 388
Tire Pressure Monitoring System
(TPMS), (USA only) 385
Child safety
Infant and child restraint systems 85
Children in the vehicle 84
Air bags 75, 86
Blocking rear door window
operation 97
Indicator lamp, Front passenger front
air bag 92
Infant and child restraint
systems 93, 95
LATCH-type child seat anchors 93
Occupant Classification System
(OCS) 88
Cigarette lighter* 321