🏷️ Basic Information

Make:

Mercedes-Benz

Model:

C-Class

Model Code:

W203

Year:

2008

👋 Introduction

Positioning:

The 2008 Mercedes-Benz C-Class (W203) represented Mercedes-Benz's entry-level luxury sedan and coupe, competing with premium compact executive cars from brands like BMW (3 Series), Audi (A4), and Lexus (IS).

Competitors 2008:

BMW 3 Series (E90/E91/E92/E93), Audi A4 (B7), Lexus IS (XE20), Infiniti G35, Acura TL.

Design:

The W203 C-Class featured a more rounded and aerodynamic design compared to its predecessor (W202), offering improved interior space and a premium feel.

Powertrains:

A range of inline-four and V6 gasoline engines, and inline-four diesel engines, paired with either a manual or automatic transmission, provided a balance of performance and efficiency.

Technology:

Introduced advanced features for its segment, including optional COMAND infotainment, Bi-Xenon headlights, and advanced safety systems like ESP and multiple airbags.

📋 Manual Details

General Coverage:

All models and all repairs A-Z for 2008 Mercedes-Benz C-Class (W203)

Estimated Page Count:

Extensive (Typically 1000+ pages for comprehensive factory service manuals)

Type:

Factory Authorized Service and Repair Manual

Language:

English

Format:

Digital (Likely PDF or similar electronic format)

📖 Manual Coverage

Engine Mechanical:

Engine assembly, cylinder head, valve train, pistons, connecting rods, crankshaft, engine block, oil pump, lubrication system, cooling system, timing components, engine mounts.

Engine Management:

Fuel injection system (EFI), ignition system, emission control systems (catalytic converter, EGR, O2 sensors), engine control module (ECM) operation, sensor diagnostics, throttle body control, variable valve timing (VVT).

Transmission Manual:

Manual transmission (if applicable) internal components, clutch system, shift linkage, transmission fluid specifications, removal and installation procedures.

Transmission Automatic:

Automatic transmission (e.g., 722.6 5-speed, 722.7 5-speed, 722.9 7-speed) internal components, valve body, torque converter, transmission control module (TCM), shift solenoids, transmission fluid specifications, removal and installation, diagnostic procedures.

Drivetrain:

Driveshafts, CV joints, differential, rear axle assembly, axle shafts, wheel bearings, propeller shaft, U-joints.

Suspension:

Front and rear suspension components, control arms, ball joints, tie rods, steering knuckles, springs, shock absorbers/struts, anti-roll bars, bushings, suspension geometry, alignment specifications.

Steering:

Power steering system, steering rack, steering column, steering wheel, power steering pump, fluid specifications, steering assist.

Brakes:

Front and rear brake systems (disc brakes), brake pads, rotors, calipers, brake lines, master cylinder, brake booster, ABS (Anti-lock Braking System) components and diagnostics, ESP (Electronic Stability Program) components and diagnostics, parking brake.

Electrical System:

12V battery, charging system (alternator), starter motor, fuse box locations and diagrams, relay functions, wiring harnesses, grounding points, electrical component testing.

Body And Interior:

Body panels, doors, hood, trunk lid, bumpers, interior trim, seats, dashboard, headliner, door panels, weatherstripping, glass, mirrors, body shell structure.

HVAC:

Heating, Ventilation, and Air Conditioning (HVAC) system, refrigerant, compressor, condenser, evaporator, blower motor, climate control module, cabin air filter, diagnostic procedures.

Comfort And Convenience:

Power windows, power locks, remote keyless entry, power seats, sunroof operation, central locking system, interior lighting, wipers and washer system.

Infotainment And Navigation:

Audio system (COMAND, Audio 20), navigation system, speakers, antenna systems, display units, control modules, Bluetooth connectivity.

Safety Systems:

Airbag system (SRS), seat belt pre-tensioners, occupant classification system, ABS, ESP, tire pressure monitoring system (TPMS), lighting systems (headlights, taillights, interior lights).

Scheduled Maintenance:

Detailed maintenance schedules based on mileage and time intervals (e.g., A Service, B Service), fluid checks and changes, filter replacements, spark plug replacement, belt inspections and replacement.

Troubleshooting:

Diagnostic trouble codes (DTCs) for various systems, symptom-based troubleshooting guides, electrical circuit tracing, common fault diagnosis.

Repair Procedures:

Step-by-step instructions for component removal, repair, and reinstallation for all major systems, including torque specifications, special tool requirements, and critical tolerances.

Component Testing:

Procedures for testing individual electrical components (sensors, actuators, modules), mechanical components (fuel injectors, ignition coils), and system performance.

Diagnostic Tools:

Information on using diagnostic scan tools (e.g., STAR Diagnosis/XENTRY), accessing control module data, performing actuations, and reading live data streams.

Wiring Diagrams:

Comprehensive electrical wiring diagrams for all vehicle systems, including component locations, connector pinouts, and wire color codes.

Depth:

Complete and comprehensive, covering basic maintenance through to complex diagnostic and repair procedures. Essential for independent repair shops and experienced DIY enthusiasts.

📊 Manual Specifications

File Format:

PDF

Quality:

High-resolution, searchable text and clear diagrams.

Binding:

N/A (Digital Format)

Paper Type:

N/A (Digital Format)

⚙️ Engine Specifications

Engine Options:

For 2008, common engines included the M271 (1.8L supercharged inline-4), M272 (2.5L/3.0L V6), and various CDI diesel engines (e.g., OM646 2.2L inline-4).

C230 Kompressor 2008:

Engine: M271.944, Displacement: 1.8L (1796cc), Horsepower: 189 hp @ 5500 rpm, Torque: 200 lb-ft @ 3000-4250 rpm.

C300 2008:

Engine: M272.961, Displacement: 3.0L (2996cc), Horsepower: 228 hp @ 6000 rpm, Torque: 221 lb-ft @ 2700-5000 rpm.

Fuel Delivery:

Electronically controlled multi-point fuel injection (MPI) or direct injection (DI) depending on specific engine variant. High-pressure fuel pump for diesel variants.

Fuel Type:

Premium Unleaded Gasoline (91 octane or higher recommended for gasoline engines), Diesel fuel for CDI models.

🔧 Transmission

Standard Transmission Type:

6-speed manual transmission (e.g., NSG370) on select models, 5-speed automatic transmission (e.g., 722.6) on most models.

Optional Transmission Type:

5-speed automatic (722.6) was standard on many models, with the 7-speed automatic (722.9 '7G-TRONIC') becoming available on higher-spec models or later in the production run of the W203 facelift. Note: 7G-TRONIC availability on 2008 W203 is less common but possible.

Automatic Features:

TouchShift manual shifting mode, Comfort (C) and Sport (S) driving modes.

📐 Dimensions

Wheelbase:

Approximately 106.7 inches (2710 mm)

Length:

Approximately 179.8 inches (4568 mm)

Width:

Approximately 68.5 inches (1740 mm)

Height:

Approximately 55.4 inches (1407 mm)

Curb Weight:

Varies by model and options, typically ranging from 3200 lbs to 3500 lbs (1450 kg to 1590 kg).

Gross Vehicle Weight Rating:

Typically around 4500 lbs to 4700 lbs (2040 kg to 2130 kg).

🛡️ Safety Features

NHTSA Ratings:

Generally received good ratings from NHTSA in its era, with 4-star or 5-star ratings for frontal and side impacts (specific ratings may vary by test date and configuration).

IIHS Ratings:

Typically rated 'Good' in IIHS frontal offset and side impact tests.

ABS:

Standard Anti-lock Braking System (ABS).

Esp:

Standard Electronic Stability Program (ESP).

Traction Control:

Standard Traction Control System (TCS).

Airbags:

Front dual-stage airbags, front side airbags, window curtain airbags (standard on most models), optional rear side airbags.

Seatbelts:

3-point inertia-reel seat belts with pre-tensioners and belt force limiters.

Child Seat Anchors:

LATCH (Lower Anchors and Tethers for Children) system.

💡 Technology Features

Infotainment Systems:

Optional COMAND (Cockpit Management and Navigation) system, featuring a central display, GPS navigation, CD player, and radio. Base models may have the Audio 20 system with similar functions but a smaller display and no integrated navigation.

Driver Assistance Features:

Cruise control, parking assist (Parktronic sensors), rain-sensing wipers, automatic climate control.

Connectivity Options:

Optional Bluetooth hands-free interface for mobile phones, voice control system (Linguatronic) on higher-end trims.

Lighting Features:

Standard halogen headlights, optional Bi-Xenon headlights with cornering illumination, LED brake lights and taillights.

🔧 Maintenance

Service A And B:

Mercedes-Benz utilizes a flexible service system. 'Service A' typically involves an oil and filter change, fluid level checks, and general inspection. 'Service B' includes these plus additional items like cabin air filter replacement, brake inspection, and potentially spark plugs or other wear items. Intervals are determined by the vehicle's 'Service Minder' system.

Engine Oil:

Typically MB 229.5 or MB 229.51 specification synthetic oil, viscosity grade 0W-40 or 5W-40 depending on climate and specific engine. Consult manual for exact grade.

Transmission Fluid Auto:

MB 236.10 or MB 236.12 specification ATF (Automatic Transmission Fluid) for the 722.6 transmission. MB 236.14 for 722.9. Refer to manual for precise type.

Coolant:

MB 325.0 or MB 325.5 specification coolant (ethylene glycol based).

Brake Fluid:

DOT 4 PLUS (or MB 331.0) specification brake fluid.

Common W203 Issues:

While the W203 is generally robust, common issues can include MAF sensor failures, oil leaks from the valve cover gasket or oil cooler seals, swirl flap actuator failure on diesel engines, transmission conductor plate issues in the 722.6, and occasional rust on body panels.

Oil Filter:

Example: Mann-Filter HU 821 x or Hengst H358WS.

Cabin Air Filter:

Example: Mann-Filter CU 25005 or Bosch 1987432198.

Spark Plug Recommendation:

Iridium spark plugs are typically recommended for M271 and M272 engines, with specific part numbers varying by engine variant. Example: NGK IFR6T11 (for some M271 variants).

📚 Vehicle History

Mercedes Benz Legacy:

Mercedes-Benz has a long-standing reputation for engineering excellence, safety, and luxury, dating back to the late 19th century. The C-Class lineage represents its commitment to providing a premium compact vehicle experience.

W203 Generation:

The W203 generation of the C-Class was produced from 2000 to 2007. The 2008 model year signifies the first year of the subsequent W204 generation, meaning this manual is for the final year of the W203 series, which received a facelift for the 2005 model year.

Production Period:

W203 generation: 2000-2007. The 2008 model year refers to the very end of this platform's production, often encompassing the final facelifted versions. This manual is specifically for the 2008 model year, which is part of the W203 lifecycle's closing stages.

Manufacturing Locations:

Primarily manufactured in Germany, with some production also occurring in other Mercedes-Benz facilities globally.

🏆 Awards & Recognition

Safety Awards:

The W203 C-Class consistently earned high safety marks in its class from independent testing organizations like IIHS and NHTSA, contributing to Mercedes-Benz's reputation for safety.

Design Awards:

While specific awards for the 2008 model are less publicized, the W203 generation was generally praised for its improved styling and interior quality compared to its predecessor.