🏷️ Basic Information Identification Make: Mercedes-Benz Model: W126 SEC Year: 1986 Codes Chassis Code: W126 Body Style Code: C126 👋 Introduction Market Position Target Audience: Mercedes-Benz W126 SEC owners, independent repair shops, automotive technicians. Competitive Analysis Differentiation: Vehicle-specific, factory-level information, not generic. Provides the exact data used by dealership technicians. Key Features Content Format: Step-by-step instructions, diagrams, illustrations, wiring schematics, and specifications. Usability: Single, easy-to-use PDF; print-on-demand functionality; no need to handle physical, potentially damaged manuals. Value Proposition Benefit To Owner: Empowers owners to perform maintenance and repairs themselves, saving time and money, and gaining a deeper understanding of their vehicle. 📋 Manual Details Coverage Areas Manual Type: Service and Repair Manual Language: English Format: PDF (Digital Download) Page Count Estimated Page Count: Extensive (Specific count not provided, but described as comprehensive, implying hundreds of pages typical for factory manuals) 📖 Manual Coverage Systems Covered Powertrain Engine: Engine Maintenance, Diagnosis, Repair, Fuel System, Emission Control, Cooling System, Lubrication System, Ignition System, Starting System, Charging System Powertrain Transmission: Automatic Transmission Service and Repair, Manual Transmission Service and Repair (if applicable to specific W126 SEC variants of that year), Clutch Service Chassis Suspension Steering: Axle, Suspension System (Front and Rear), Steering Column, Power Steering System, Tire and Wheel Specifications Chassis Brakes: Brake Control System, Brake System (Hydraulic, Disc/Drum), Parking Brake System Electrical Electronics: Electrical System, Wiring Schematics, Multiplex/CAN Communication (early forms), Meter/Audio/Visual Systems, Cruise Control, Horn, Wiper & Washer System, Door Lock System, Engine Immobilizer (if equipped) Body Interior Exterior: Body Repairs, Exterior and Interior Trim, Engine Hood/Door Operation and Repair, Windshield/Glass/Mirror Replacement, Instrument Panel, Seats, Supplemental Restraint System (SRS) / Airbags, Seat Belts HVAC: Air Conditioning System Service and Repair Procedures Included Maintenance: Routine Maintenance, Scheduled Service Intervals, Fluid Checks and Replacements, Filter Replacements, Tune-ups Diagnostics: Systematic Troubleshooting, Fault Diagnosis Procedures, Diagnostic Trouble Codes (if applicable to the era) Repair: Component Repair, System Overhaul, Major Component Reassembly, Rebuild Procedures Installation: Component Replacement, Accessory Installation Guidance Technical Depth Depth: Factory-level, comprehensive, covering all repairs from basic maintenance to complex diagnostics and component overhauls. 📊 Manual Specifications File Format File Type: PDF Compatibility: Windows Vista (32/64-bit), XP, ME, 98, NT, 2000; macOS Compatible Software Requirements: Adobe PDF Reader, Winzip (or equivalent extraction utility) Print Quality Printability: All pages are printable, allowing for enlarged image printing and selective page printing. Binding Type Binding: Digital (No physical binding) Paper Type Paper Type: N/A (Digital format) ⚙️ Engine Specifications Primary Engine Engine Type 1986 W126 Sec: V8 Gasoline (M116 or M117 engine family) Displacement Liter Typical: 5.0L (500 SEC) Fuel System: Bosch K-Jetronic (CIS - Continuous Injection System) or potentially early electronic fuel injection (KE-Jetronic) depending on specific market and final production date within 1986. Performance Horsepower Approx 5.0L: ~230-240 hp (SAE Gross) Torque Approx 5.0L: ~280-300 lb-ft (SAE Gross) 🔧 Transmission Standard Transmission Type: 4-Speed Automatic Transmission (e.g., 722.3 or 722.4) Optional Optional Transmission: Not typically offered for the SEC Coupe model in this era; manual transmission was not a factory option for the W126 SEC. Features Torque Converter Lockup: Yes, standard feature on automatic transmissions of this era for improved efficiency. 📐 Dimensions Exterior Body Style: 2-door Coupe Weights Curb Weight Approx: ~3,800 - 4,000 lbs (depending on engine and options) 🛡️ Safety Features Passive Features Seat Belts: Driver and passenger front seat belts, possibly rear seat belts. Supplemental Restraint System: Driver's side airbag became increasingly common in this period, check specific vehicle for availability. 💡 Technology Features Infotainment Audio System: Factory AM/FM stereo with cassette player, often with multi-speaker system. Aftermarket upgrades were common. Driver Assistance Cruise Control: Standard feature on SEC models. Comfort Features Climate Control: Automatic Climate Control (optional or standard depending on trim), often with vacuum-actuated servo system. Windows Mirrors: Power windows, power mirrors, power antenna. 🔧 Maintenance Service Intervals Oil Change Interval: Typically every 5,000-7,500 miles or annually, depending on driving conditions and oil used. Consult specific manual for exact factory recommendations. Transmission Fluid Change: Often recommended around 30,000-60,000 miles, but many vehicles of this age have never had it done; consult manual for specific procedure and fluid type. Fluid Specifications Engine Oil Specification: API SF or SG rating, SAE 10W-30 or 10W-40 recommended for most climates. Specific viscosity may vary with temperature. Always verify with manual. Transmission Fluid Type: Dexron II or equivalent is a common specification for this era Mercedes automatic transmission. Crucial to use the correct fluid type. Coolant Type: Ethylene Glycol based coolant, typically a 50/50 mix with distilled water. Specific Mercedes-Benz specifications may apply. Known Issues Common Wear Items: Fuel distributor seals (K-Jetronic), vacuum hoses, ignition components (spark plugs, wires, distributor cap/rotor), fuel pumps, suspension bushings, climate control servos, blower motor resistor. Electrical Gremlins: Common in older vehicles due to age; degraded wiring insulation, failing relays, and control unit issues can occur. 📚 Vehicle...