🏷️ Basic Information

Make:

Mercedes-Benz

Model:

C-Class

Body Style:

Coupe & Saloon (Sedan)

Generation Code:

W203

Internal Chassis Codes:

W203 (Saloon), CL203 (Sportcoupe/Coupe)

👋 Introduction

Segment:

Entry-level luxury compact car

Key Competitors:

BMW 3 Series (E46/E90), Audi A4 (B6/B7), Lexus IS, Acura TL

Distinguishing Attributes:

High build quality, comfortable ride, premium interior, advanced safety features for its era, range of efficient and powerful engines

📋 Manual Details

Covered Years:

2001, 2002, 2003, 2004, 2005, 2006, 2007

Estimated Page Count:

~3000-5000+ (varies by specific engine/trim content)

Type:

Complete Workshop Service and Repair Manual

Language:

English

Format:

Downloadable Digital Format (typically PDF)

📖 Manual Coverage

Engine Mechanical:

Engine assembly, cylinder head, crankshaft, pistons, connecting rods, timing, lubrication, cooling, fuel delivery, emission controls (detailed for M271, M112, M272, OM611, OM612, OM646, OM647 variants)

Engine Management:

ECU operation, sensor diagnostics, ignition system, fuel injection (CRIME, HEGO sensors, MAF, etc.)

Transmission Manual:

Manual gearbox operation, clutch, shifter mechanism

Transmission Automatic:

Automatic transmission (e.g., 722.6 '5G-TRONIC') operation, valve body, torque converter, electronic control, fluid and filter service

Drivetrain:

Driveshafts, CV joints, differential, rear axle assembly

Suspension:

Front and rear suspension components (struts, control arms, bushings, springs, anti-roll bars), wheel alignment specifications

Steering:

Power steering system (hydraulic), steering column, steering rack, tie rod ends, troubleshooting

Brakes:

Brake system (front and rear discs), ABS, EBD, Brake assist (BAS), parking brake, fluid specifications, bleeding procedures

Electrical System:

12V battery, alternator, starter motor, fuses, relays, wiring diagrams (comprehensive for lighting, power windows, locks, seats, mirrors, etc.)

Climate Control:

HVAC system, A/C compressor, refrigerant handling, climate control module, blower motor, cabin filter replacement

Body Exterior:

Body panels, doors, hood, trunk, bumpers, glass, seals, exterior trim, corrosion protection

Body Interior:

Dashboard, seats, headliner, door panels, carpeting, interior trim, SRS airbag system components (excluding airbag module diagnostics typically)

Infotainment Navigation:

Audio system, navigation unit (COMAND), telematics, speaker replacement

Routine Maintenance:

Oil changes, filter replacements (oil, air, fuel, cabin), spark plug replacement, fluid checks and top-offs

Engine Repair:

Head gasket replacement, timing belt/chain service, piston ring replacement, valve adjustment (if applicable), component reassembly

Transmission Service:

Fluid and filter changes, clutch replacement, transmission overhaul procedures

Brake System Repair:

Brake pad/rotor replacement, caliper overhaul, brake line replacement, ABS component replacement

Suspension Steering Repair:

Strut/shock absorber replacement, control arm bushing replacement, steering rack replacement, power steering pump replacement

Electrical Troubleshooting:

Diagnosis of electrical faults using wiring diagrams, component testing, common electrical system issues

Bodywork Repair:

Panel removal/installation, door adjustment, glass replacement, bumper repair

Diagnostic Procedures:

Troubleshooting charts, fault code explanations (OBD-II where applicable), testing procedures for various systems

Technical Specifications:

Torque specifications for all fasteners, fluid capacities, gap settings, measurements

Depth:

Comprehensive from basic maintenance to full engine and transmission overhauls, including electrical diagnostics and body repair

📊 Manual Specifications

Digital Format:

PDF (Portable Document Format)

Resolution:

High-resolution, printable pages with clear diagrams and text

Binding:

N/A (Digital download)

Paper Quality:

N/A (Digital download)

Text Search:

Searchable text enabled (typically)

⚙️ Engine Specifications

Engine Code 1:

M271 (e.g., C180 Kompressor, C200 Kompressor)

Displacement 1:

1.8 L (1796 cc)

Configuration 1:

Inline-4 (Supercharged)

Horsepower 1:

143-192 hp (depending on variant)

Torque 1:

220-270 Nm (depending on variant)

Engine Code 2:

M112 (e.g., C240, C320)

Displacement 2:

2.6 L (2597 cc) / 3.2 L (3199 cc)

Configuration 2:

V6 (Naturally Aspirated)

Horsepower 2:

170 hp (2.6L) / 215-224 hp (3.2L)

Torque 2:

245 Nm (2.6L) / 310-315 Nm (3.2L)

Engine Code 3:

M272 (Later 2005+ models, e.g., C230, C350)

Displacement 3:

2.5 L (2496 cc) / 3.5 L (3498 cc)

Configuration 3:

V6 (Naturally Aspirated)

Horsepower 3:

201-215 hp (2.5L) / 268-272 hp (3.5L)

Torque 3:

245 Nm (2.5L) / 350-353 Nm (3.5L)

Engine Code Diesel 1:

OM611 (e.g., C200 CDI, C220 CDI)

Displacement Diesel 1:

2.1 L (2148 cc)

Configuration Diesel 1:

Inline-4 (Turbocharged Diesel - Common Rail)

Horsepower Diesel 1:

102-143 hp (depending on variant)

Torque Diesel 1:

235-315 Nm (depending on variant)

Engine Code Diesel 2:

OM646 (Facelift models, e.g., C200 CDI, C220 CDI)

Displacement Diesel 2:

2.2 L (2148 cc)

Configuration Diesel 2:

Inline-4 (Turbocharged Diesel - Common Rail, improved)

Horsepower Diesel 2:

122-150 hp (depending on variant)

Torque Diesel 2:

270-340 Nm (depending on variant)

0-60 Mph Typical:

6.5 - 9.5 seconds (depending on engine)

Injection Type:

Multi-point fuel injection (MPI) for petrol, Common Rail Direct Injection (CDI) for diesel

🔧 Transmission

Transmission Type Std:

5-speed Manual (Getrag 235/5)

Transmission Type Opt:

5-speed Automatic (722.6 '5G-TRONIC'), 6-speed Automatic (722.9 '7G-TRONIC' - introduced later)

Automatic Features:

Touchshift (manual selection), Comfort/Sport modes

📐 Dimensions

Length Saloon:

~4525 mm

Length Coupe:

~4527 mm

Width:

~1728 mm

Height:

~1400-1420 mm (Saloon) / ~1370 mm (Coupe)

Wheelbase:

~2715 mm

Curb Weight:

~1450-1650 kg (depending on engine/options)

🛡️ Safety Features

Euro Ncap Rating:

4 Stars (initial, later models improved)

Active Safety:

ABS, EBD, Brake Assist (BAS), ESP (Electronic Stability Program)

Passive Safety:

Front airbags, side airbags, curtain airbags (optional/later models), front and rear seatbelt pre-tensioners

💡 Technology Features

Infotainment System:

Audio 20 (standard), COMAND APS (optional with navigation), CD changer, harman/kardon audio system

Driver Assistance Features:

Cruise control, Rain-sensing wipers, Auto-dimming rearview mirror, Parktronic (optional parking sensors)

Connectivity Options:

Optional Bluetooth hands-free system (often via cradle), UHI interface for phone modules

Bi Xenon Headlights:

Optional Bi-Xenon headlamps with dynamic cornering assist

🔧 Maintenance

Oil Change Interval:

Typically every 10,000-15,000 miles or 12 months, whichever comes first (flexible service system - ASSYST)

Major Service Interval:

Refer to manual for detailed service B (e.g., spark plugs, transmission fluid, brake fluid based on mileage/time)

Engine Oil Petrol:

MB 229.5 or 229.51 (e.g., Mobil 1 0W-40, Castrol EDGE 0W-40)

Engine Oil Diesel:

MB 229.51 or 228.51 (e.g., Mobil 1 ESP Formula 5W-30)

Transmission Fluid Auto:

MB 236.14 (e.g., Shell ATF 134, Pentosin ATF 9)

Coolant:

MB 325.0 or 326.0 (Antifreeze/Coolant Concentrate - blue/green)

Brake Fluid:

DOT 4 Plus (MB Spec 331.0)

Common Problems Petrol:

Oil leaks from valve cover gasket/oil cooler, ignition coil failures, MAF sensor issues, camshaft position sensor failures, timing chain tensioner wear (M271 Kompressor), biodegrading wiring harness insulation (specific VIN ranges).

Common Problems Diesel:

Glow plug failure, injector issues, EGR valve clogging, turbocharger problems, swirl flap issues (OM611/646).

Common Problems General:

Front lower ball joint wear, rear subframe bushings, water pump leaks, climate control flap actuators, ABS sensor failures, power steering pump whine.

📚 Vehicle History

Mercedes Benz Legacy:

Long history of producing robust, reliable, and technologically advanced vehicles, particularly in the executive and luxury segments.

W203 Introduction:

Introduced in 2000 (for MY2001) as a replacement for the W202 C-Class. Represented a significant styling and technological update, moving towards a more rounded and contemporary design language. The 'Sportcoupe' (CL203) variant was introduced in 2001, later evolving into the CLC-Class. A facelift occurred for the 2005 model year, introducing updated styling, new engines, and improved features.

Manufacturing Plants:

Primary production in Sindelfingen, Germany. Also produced in other Mercedes-Benz plants globally.

🏆 Awards & Recognition

Industry Awards:

While specific awards for this exact generation are less prominently cited than some other Mercedes models, the C-Class consistently ranked well in customer satisfaction surveys and received positive reviews from automotive publications for its blend of luxury, comfort, and performance.