Vehicle Segment:
Compact Executive Car (C-Segment)
Vehicle Niche:
Sportcoupé (CL203 variant), targeting younger buyers and those seeking a more dynamic C-Class experience.
Key Competitors:
BMW 3 Series Compact, Audi A3, Volkswagen Golf GTI, Alfa Romeo 147
Brand Prestige:
Leverages Mercedes-Benz's reputation for quality, safety, and engineering.
Sporty Styling:
CL203's distinctive 3-door hatchback-like profile with a more raked rear end.
Manual Value Proposition:
Provides essential DIY repair and maintenance information, crucial for cost-effective ownership of a premium vehicle.
Covered Model Years:
2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
Covered Body Styles:
CL203 (Sportcoupé)
Estimated Page Count:
Extensive (typically 2000+ pages for a complete comprehensive manual)
Manual Type:
Workshop Service and Repair Manual
Digital Format:
Downloadable (likely PDF)
Powertrain:
Engine mechanical, engine electrical, fuel system, exhaust system, cooling system, lubrication system
Drivetrain:
Transmission (manual & automatic), clutch, driveshafts, differentials, axles
Chassis:
Suspension (front & rear), steering, brakes (hydraulic & ABS), wheels & tires
Electrical Systems:
Battery, charging system, starter, lighting, instruments, wipers, horn, power accessories, comfort systems (HVAC), CAN bus communication
Body:
Body construction, interior trim, exterior trim, doors, windows, locks, seats, safety restraint systems (airbags, seatbelts)
Maintenance Procedures:
Scheduled maintenance, fluid changes, filter replacements, inspections
Repair Procedures:
Component removal, installation, overhaul, and replacement for all major systems
Diagnostics Troubleshooting:
Fault finding charts, symptom-based diagnosis, diagnostic trouble codes (DTCs), electronic system diagnostics
Specifications Tolerances:
Torque specifications, clearances, fluid capacities, electrical values, diagnostic parameters
Depth:
Comprehensive: Covers routine maintenance, in-depth diagnostics, component-level repairs, and major system overhauls.
Engine Range:
M271 (1.8L Supercharged Inline-4), M111 (2.0L Supercharged Inline-4), M272 (2.5L/3.0L V6), M112 (2.6L/3.2L V6 - early models)
C180 Kompressor (M271 E18Ml):
1.8L, 143 hp @ 5200 rpm, 220 Nm @ 3500-4500 rpm
C200 Kompressor (M271 E20Ml):
2.0L, 163 hp @ 5300 rpm, 240 Nm @ 3000-4000 rpm
C230 Kompressor (M271 E23Ml):
2.3L, 192 hp @ 5300 rpm, 270 Nm @ 3100-4500 rpm
C32 Amg Kompressor (M112 E32Ml De32):
3.2L Supercharged V6, 354 hp @ 6100 rpm, 450 Nm @ 3000-4000 rpm
Fuel Delivery:
Electronic Fuel Injection (EFI) with multi-point injection (MPI)
Fuel Type:
Unleaded gasoline (Premium required for most variants)
Common Engine Codes:
M271.920, M271.940, M271.942, M111.951, M112.910, M112.912, M272.920, M272.940, M112.917 (AMG)
Manual Options:
6-speed manual (e.g., Getrag 260/6)
Automatic Options:
5-speed automatic (e.g., 5G-Tronic 722.6), 7-speed automatic (e.g., 7G-Tronic 722.9 for later models/higher trims)
Automatic Modes:
Comfort (C) and Sport (S) modes
Automatic Transmission Fluid:
MB 236.10, 236.12, 236.14 (depending on transmission type and year)
Manual Transmission Fluid:
MB 235.10, 235.4 (GL-4 or GL-5 rated gear oil, specific viscosity)
Length:
Approx. 4,165 mm (163.9 in) for CL203 Sportcoupé
Width:
Approx. 1,728 mm (68.0 in)
Height:
Approx. 1,405 mm (55.3 in)
Wheelbase:
Approx. 2,715 mm (106.9 in)
Cargo Volume:
Approx. 310 - 1120 liters (10.9 - 39.6 cu ft) for CL203
Curb Weight:
Approx. 1,400 - 1,600 kg (3,086 - 3,527 lbs), varies significantly by engine and equipment
Euro Ncap:
Likely achieved 4 or 5 stars for adult occupant protection (testing standards evolved during model run)
Standard Active Safety:
ABS (Anti-lock Braking System), ESP (Electronic Stability Program, often called ESP or ASR), Brake Assist (BAS)
Optional Active Safety:
Traction Control System (ASR), Cruise Control
Standard Passive Safety:
Front airbags, side airbags (front), window airbags, pre-tensioning seatbelts with force limiters
Body Structure:
High-strength steel body structure, crumple zones
Audio System:
Optional COMAND (Cockpit Management and Navigation Display) system with CD player, radio, optional navigation, and early Bluetooth integration. Standard Audio 20 systems available.
User Interface:
COMAND systems typically controlled via a rotary knob and buttons on the center console.
Optional Features:
Parktronic (parking sensors), Rain-sensing wipers, Auto-dimming rearview mirror, Bi-Xenon Headlights (often with cornering function on facelift models).
Connectivity Options:
Early Bluetooth telephony (hands-free calling), optional CD changer.
Oil Change Interval:
Typically every 15,000 km (9,300 miles) or 12 months, whichever comes first, using synthetic oil (e.g., MB 229.5).
Air Filter Replacement:
Every 30,000 km (18,600 miles) or as needed based on driving conditions.
Spark Plug Replacement:
Iridium spark plugs typically last 100,000 km (60,000 miles).
Transmission Fluid Service:
Automatic: Around 60,000 - 100,000 km (37,000 - 60,000 miles) depending on oil spec and driving. Manual: Check manufacturer recommendation, often longer intervals or lifetime fill.
Engine Oil Spec:
MB-Approval 229.5 (e.g., Mobil 1 0W-40, Castrol Edge 0W-40), or 229.3/229.31 for older/specific models. Always verify with VIN.
Coolant Spec:
MB-Approval 325.0 or 326.0 (Antifreeze/Coolant, ethylene glycol-based, blue or green color)
Brake Fluid Spec:
DOT 4 (MB-Approval 331.0 or equivalent)
Common Faults M271:
Timing chain stretch/tensioner failure, crankcase ventilation (PCV) system issues, oil leaks from camshaft adjusters (camphasizer) and seals, ignition coil failures.
Common Faults Suspension Steering:
Worn front control arm bushings, ball joints, tie rod ends, and rear axle bushings leading to noise and poor handling.
Common Faults Electronics:
Malfunctioning climate control flaps, ESP/ABS sensor issues, power window regulator failures, SAM (Signal Acquisition Module) unit issues.
Common Faults Other:
Rust on wheel arches, sills, and rear window surround (especially pre-facelift), catalytic converter failures, fuel pump issues.
Brand Founding:
1926 (merger of Benz & Cie. and Daimler-Motoren-Gesellschaft)
Engineering Philosophy:
Known for pioneering safety features, robust engineering, and luxury.
C Class Predecessors:
W201 (190E/190D), W202 (C-Class)
W203 Generation Introduction:
Introduced in 2000 for the 2001 model year, replacing the W202. The CL203 Sportcoupé variant launched in 2001.
Facelift:
A significant facelift occurred for the 2005 model year, introducing updated styling, engines, and technology (often referred to as the 'Phase 2' or 'W203 facelift'). This manual covers both pre-facelift and facelifted models.
Production Locations:
Primarily Sindelfingen, Germany; also South Africa, Malaysia, China (depending on market)
Production End Year For W203:
2007 (replaced by the W204 C-Class for the 2008 model year in most markets)
J D Power Initial Quality:
While specific ratings for the CL203 are less prominent, the W203 generation generally performed reasonably well in initial quality surveys for its segment during its early years.
Safety Ratings:
Consistently aimed for high safety ratings in its class, reflecting Mercedes-Benz's commitment to safety.
