🏷️ Basic Information Identification Make: Mercedes-Benz Model: S-Class Chassis Code: W221 Model Year: 2009 Generation Generation Name: Fourth Generation Generation Years: 2005-2013 👋 Introduction Market Position Market Segment: Ultra-luxury sedan, flagship model of Mercedes-Benz. Competitive Analysis Competitors: BMW 7 Series, Audi A8, Lexus LS, Porsche Panamera. Key Features Defining Attributes: Unparalleled ride comfort, advanced safety and driver assistance technologies, sophisticated interior design and materials, powerful yet refined powertrains. Target Audience: Discerning individuals seeking the pinnacle of automotive luxury, comfort, and technological innovation. 📋 Manual Details Coverage Areas Coverage Description: Comprehensive service, repair, and diagnostic procedures for the 2009 Mercedes-Benz S-Class W221, including all major mechanical, electrical, and body systems. Covers routine maintenance, troubleshooting, component replacement, and specialized repairs. Page Count Estimated Page Count: Over 3000 pages (typical for full factory service manuals of this era and complexity) Manual Type Manual Type: Factory Service Repair Workshop Manual Language Language: English Format Format: Digital Download (PDF) 📖 Manual Coverage Systems Covered Engine Mechanical: Engine assembly, cylinder head, valve train, crankshaft, pistons, connecting rods, lubrication system, cooling system, engine management. Engine Management Electronics: Engine Control Unit (ECU) functions, sensor data, actuators, ignition system, fuel injection system, emissions control. Transmission Mechanical: Automatic transmission assembly (e.g., 7G-TRONIC), torque converter, planetary gear sets, hydraulic controls, clutch packs. Transmission Electronics: Transmission Control Unit (TCU), gear selection logic, shift solenoids, mechatronics unit. Drivetrain: Front axle, rear axle, drive shafts, differential, propeller shafts, transfer case (if applicable). Suspension: AIRMATIC dual control air suspension, Active Body Control (ABC) system, independent suspension components, control arms, ball joints, shock absorbers, air springs. Steering: Power steering system, steering column, steering gear, electronic power steering (EPS) components. Brakes: Hydraulic braking system, ABS (Anti-lock Braking System), ESP (Electronic Stability Program), brake boosters, master cylinder, brake calipers, rotors, brake pads, parking brake system (electronic). Electrical System: 12V battery system, alternator, starter motor, wiring diagrams for all circuits, fuse boxes, relays. Body And Chassis: Body structure, doors, hood, trunk, bumpers, interior trim, exterior trim, noise insulation. Comfort And Convenience: Climate control system (THERMOTRONIC), power windows, power seats, sunroof, central locking, keyless entry, power trunk, soft-close doors. Infotainment And Navigation: COMAND (Cockpit Management and Navigation) system, audio system, navigation unit, telephone integration, media interface. Lighting: Headlights (bi-xenon, LED), taillights, interior lighting, fog lights, ambient lighting, headlight aiming. Safety Systems: AIRBAG system, seat belt pretensioners, occupant classification system, ABS, ESP, ADAPTIVE BRAKE, PRE-SAFE® system. Driver Assistance: DISTRONIC PLUS (adaptive cruise control), PARKTRONIC (parking assist), LANE KEEPING ASSIST, BLIND SPOT ASSIST, NIGHT VIEW ASSIST. Procedures Included Routine Maintenance: Oil changes, filter replacements (oil, air, cabin), fluid checks and top-offs, spark plug replacement, tire rotation, brake pad inspection. Troubleshooting: Diagnostic fault codes (DTCs), symptom-based troubleshooting guides, electrical circuit diagnosis, mechanical component diagnosis. Component Replacement: Detailed instructions for replacing major components like engine, transmission, starter, alternator, fuel pump, brake calipers, suspension struts, control modules. Rebuilding Procedures: Major overhaul procedures for engines and transmissions, including disassembly, inspection, component replacement, and reassembly. Calibration And Adjustment: Calibration of sensors (e.g., steering angle sensor, ride height sensors), alignment procedures, seat calibration, key programming. Diagnostic Tool Usage: Information on using Mercedes-Benz specific diagnostic tools (e.g., STAR DIAGNOSIS/XENTRY) for system analysis and module programming. Technical Depth Depth Of Information: Factory-level technical depth, including detailed schematics, torque specifications, clearances, diagnostic procedures, and component data. 📊 Manual Specifications File Format File Format: PDF Searchability: Searchable text content for quick information retrieval. Print Quality Print Quality: High-resolution, suitable for professional printing or on-screen viewing. Binding Type Binding Type: N/A (Digital Download) Paper Type Paper Type: N/A (Digital Download) ⚙️ Engine Specifications Primary Engine Engine Options 2009: S350 (3.5L V6 M272), S550 (5.5L V8 M273), S600 (5.5L V12 Bi-Turbo M275), S63 AMG (6.2L V8 M156), S65 AMG (6.0L V12 Bi-Turbo M275). Engine Code S550: M273 Performance S550 Horsepower: 382 hp @ 6000 rpm S550 Torque: 391 lb-ft @ 2800-4500 rpm Fuel System Fuel Type: Premium Unleaded Gasoline (91 octane or higher recommended) Injection Type: Sequential Multi-Port Fuel Injection (MPI) or Direct Injection (DI) depending on specific engine variant. Engine Management Engine Control Module: ME-SFI / ECM (Engine Control Module) / ECU 🔧 Transmission Standard Transmission Type S550: 7-speed automatic (7G-TRONIC) Optional All Wheel Drive: 4MATIC all-wheel drive available on select models (e.g., S550 4MATIC). Features Transmission Modes: Comfort (C) and Sport (S) modes. Fluid Specification Transmission Fluid Type: MB Approved Automatic Transmission Fluid (ATF) such as MB 236.14 (e.g., Pentosin ATF1 or equivalent). Fluid Capacity Transmission Fluid Capacity 7G Tronic: Approx. 9 liters (2.4 US gallons) for a dry fill, consult manual for specific service fill. 📐 Dimensions Exterior Wheelbase: 3165 mm (124.6 in) Overall Length: 5207 mm (205.0 in) Overall Width: 1871 mm (73.7 in) Overall Height: 1477 mm (58.1 in) Weights Curb Weight S550: Approx. 1990 kg (4387 lbs) Gross Vehicle Weight Rating: Consult vehicle placard Wheels And Tires Standard...