
ContentsFuels, coolants, lubricants etc. ..........  329
Capacities ....................................  329
Engine oils ....................................  332
Engine oil additives ......................  332
Air conditioning refrigerant ..........  332
Brake fluid ....................................  332
Premium unleaded gasoline .........  333
Fuel requirements ........................  333
Gasoline additives ........................  334
Flexible Fuel Vehicles ...................  334
Coolants .......................................  336
Windshield washer and 
headlamp cleaning* system .........  338
Consumer information .......................  339
Uniform tire quality grading..........  339
Technical terms...............................  341Index.................................................  347 

332 Technical dataFuels, coolants, lubricants etc.Engine oils
Engine oils are specifically tested for their 
suitability in our engines. Therefore, use 
only engine oils recommended by 
Mercedes-Benz. Information on 
recommended brands is available in the 
Factory Approved Service Products pam-
phlet, or at your authorized Mercedes-Benz 
Center.
Please follow FSS recommendations for 
scheduled oil changes. Failure to do so 
could result in engine damage not covered 
by the Mercedes-Benz Limited Warranty.
Engine oil additives
Do not blend oil additives with engine oil. 
They may be harmful to the engine opera-
tion.
Damage or malfunctions resulting from 
blending oil additives are not covered by 
the Mercedes-Benz Limited Warranty.Air conditioning refrigerant
R-134a (HFC) refrigerant and special PAG 
lubricating oil is used in the air condition-
ing system.
Never use R-12 (CFC) or mineral-based 
lubricating oil, otherwise damage to the 
system will occur.
Brake fluid
During vehicle operation, the boiling point 
of the brake fluid is continuously reduced 
through the absorption of moisture from 
the atmosphere. Under extremely strenu-
ous operating conditions, this moisture 
content can lead to the formation of bub-
bles in the system, thus reducing the sys-
tem’s efficiency.
Therefore, the brake fluid must be 
replaced every two years, preferably in the 
spring.
Only brake fluid approved by 
Mercedes-Benz is recommended. Your 
authorized Mercedes-Benz Center will 
provide you with additional information. 

334 Technical dataFuels, coolants, lubricants etc.Gasoline additives
A major concern among engine manufac-
turers is carbon build-up caused by gaso-
line. Mercedes-Benz recommends only the 
use of quality gasoline containing additives 
that prevent the build up of carbon depos-
its.
After an extended period of using fuels 
without such additives, carbon deposits 
can build up especially on the intake valves 
and in the combustion area, leading to en-
gine performance problems such as:
Warm-up hesitation
Unstable idle
Knocking/pinging
Misfire
Power loss
Do not blend any specific fuel additives 
with fuel. This only results in unnecessary 
cost and may be harmful to engine opera-
tion.Damage or malfunctions resulting from 
poor fuel quality or from blending specific 
fuel additives are not covered by the 
Mercedes-Benz Limited Warranty.
Flexible Fuel Vehicles
MY 2003 Mercedes-Benz C 320 models, 
except those equipped with manual trans-
mission or 4MATIC*, are Flexible Fuel Ve-
hicles.
These vehicles are designed to operate on 
premium unleaded gasoline or Ethanol 
fuel (E85), or on any mixture of these two.
Ethanol fuel (E85) is a mixture of approxi-
mately 85% Ethanol and 15% unleaded 
gasoline.Switching fuels
For best performance and driveability it is 
recommended to use either one or the 
other fuel. A refueling pattern that 
alternates between the two different fuels 
should be avoided if possible.
Warning!
G
Ethanol fuel (E85) and its fumes are highly 
flammable, poisonous and burn easily. Etha-
nol fuel can cause serious injuries if ignited 
or if you come into contact with it or inhale 
fumes of it. Avoid inhalation of Ethanol 
fumes and skin contact with Ethanol. Extin-
guish all open flames before fueling. Never 
smoke or create sparks close to Ethanol. 

354 Index
Messages in display 269
Switching off 76
Switching on 77
Warning lamp 256
ETD 64, 342
Safety guidelines 59
Ethanol fuel
At the gas station 233
Requirements 334
Switching fuels 334
Exterior lamp switch 47, 101
Exterior lamps
Delayed shut-off 126
Exterior rear view mirrors
Adjusting 39
Parking position* for 131
F
Fahrenheit
Setting temperature units 123
Fastening the seat belts 41
Fine adjustment
Cruise control 195
First aid kit 279
Flat tire 297
Lowering the vehicle 301
Mounting the spare wheel 297Preparing the vehicle 297
Spare wheel 281
Flexible fuel vehicles 334
At the gas station 233
Switching fuels 334
Flexible Service System (FSS) 247, 342
Fog lamp, rear 103, 291
Fog lamps
Replacing bulbs 290
Fog lamps, front 103
Messages in display 274
Replacing bulbs 291
Switching on 103
Four wheel electronic traction system 
(4MATIC) with ESP 78
4MATIC 78
Front airbags 60
Front lamps
Bi-Xenon type* 293
Halogen-type 292
Messages in display 272–275
Replacing bulbs 290, 292
Switching on 101
Front seat head restraints
Installing 94
Manual seat 94Power seat* 94
Removing 94
Front seats
Heater* 97
FSS (Flexible Service System) 247, 342
Fuel 234
Additives 334
Cruising range 335
E85 (Ethanol fuel) 335
Fuel reserve warning lamp 259
Gasoline additives 334
Premium unleaded 
gasoline 234, 330, 333
Requirements 333, 334
Reserve warning 23
Switching (Flexible fuel vehicle) 334
Technical data 329
Fuel additives 334
Fuel consumption statistics
After start 132
Since last reset 132, 133
Fuel filler flap 233
Locking 233
Opening 287
Unlocking 233 

355 Index
Fuel requirements 333
For ethanol fuel 334
Fuel reserve tank
Message in display 272
Fuel tank
Capacity 330
Filler flap 233
Fuels, coolants, lubricants etc.
Capacities 329
Functions (control system) 112, 115
Resetting 120
Fuse box 312
Fuse chart 312
Fuse extractor 313
Fuses 312
Auxiliary fuse box in the trunk 313
F us e box in e ng ine com pa rtm ent 3 12
Fuse box in passenger 
compartment 312
Fuse chart 312
Fuse extractor 313
Spare fuses 313G
Garage door opener 27, 217
Erasing in remote control 220
Integrated remote control 218
Rolling code programming 219
Gasoline see Fuel 234
Gasoline additives 334
Gear range 342
Automatic transmission 140
Limiting 140
Shifting into optimal 139
Gear range limit
Canceling 139
Gear selector lever
Cleaning 252
Position 141
Global
Locking 85
Unlocking 85
Global Positioning System (GPS) 342
Glove box 21, 203
Closing 203
Opening 203
Good visibility 144
GPS 342
GPS see COMAND* 210H
Halogen-type
Front lamp bulbs 292
Hand-held transmitter
Programming integrated remote 
control 218
Hands-free microphone 27
Hard plastic trim items
Cleaning 252
Hazard warning flasher 104
Switching off 104
Switching on 104
Head restraints 94
Manual seats 33
Power seats* 35
Rear seats 35
Headlamp cleaning system* 241
Headlamp shut-off delay 
see Delayed shut-off, exterior lamps
Headlamps
Automatic control 102
Bi-Xenon type*
Replacing bulbs 293
Bi-Xenon* 341
Cleaning 251
Cleaning system* 146, 241, 338 

367 Index
Technical data 332
Brake fluid 332
Coolant 329
Coolants 336
Electrical system 326
Engine oil 332
Engine oil additives 332
Flexible fuel vehicles 334
Fuel requirements 333
Fuels 329
Gasoline additives 334
Lubricants 329
Main dimensions 327
Premium unleaded gasoline 333
Rims and tires 322
Weights 328
Windshield washer and headlamp 
cleaning* system 331, 338
Tele Aid* 209
Emergency calls 211
Information 214
Initiating an emergency call 
manually 212
Messages in display 277
Remote door unlock 216
Roadside assistance 213SOS button 212
Stolen vehicle tracking services 217
System self-check 210
Tele Aid System 210, 345
Upgrade signals 215
Telematics* 345
Telephone* 24, 208
Answering a call 135
Dialing a number from 
the phone book 135
Emergency call 185
Ending a call 135
Hands-free microphone 27
Loading phone book* 135
Messages in display 277
Operation 134, 182
Redialing 136
Signal strength 134
Temperature
Display mode 123
Grades of tires 340
Setting interior 
temperature 150, 158
Setting units in display 123
Tires 244Tightening torque 
(Wheel bolts) 301, 345
Tilt
Head restraint 34
Time
Setting hours 122
Setting minutes 122
Time display
Setting 123
Tire inflation pressure
Checking 234, 243
Tire speed rating 227, 345
Tire traction 227
Tires 242, 322, 339
Consumer information 339
Direction of rotation 243
Driving instructions 226
Retreads 242
Rims and tires 322
Service life 243
Temperature 244
Temperature grades 340
Tread depth 245
Wear pattern 244
Winter 245
Tools 279