This comprehensive service and repair manual covers all models of the Mercedes W126 SEC, from 1979 to 1992. It provides the same detailed information used by technicians at Mercedes dealerships to maintain, service, diagnose, and repair your vehicle. This manual is not generic repair information; it is vehicle-specific, ensuring you have the accurate instructions and diagrams needed for your specific model.

Inside, you'll find step-by-step instructions, diagrams, illustrations, wiring schematics, and specifications for every aspect of your car. You'll gain a thorough understanding of your vehicle and confidently tackle a wide range of repairs, from basic maintenance to complex mechanical issues.

The manual covers all essential systems, including:

* **Engine:** Includes information on engine maintenance, repairs, and troubleshooting.
* **Control System:** Covers the intricate workings of the engine control system, helping you understand and address any issues.
* **Mechanical Systems:** Provides detailed instructions for repairing and maintaining the mechanical components of your car, such as the transmission, drive shaft, differential, and axles.
* **Fuel Service Specifications:** Offers precise specifications for fuel systems, ensuring you use the correct fluids and components for optimal performance.
* **Emission Control:** Details on emission control systems to ensure your vehicle meets environmental standards.
* **Intake, Exhaust, and Cooling:** Covers all aspects of these critical systems, including maintenance, repairs, and troubleshooting.
* **Lube:** Provides guidance on proper lubrication practices to keep your engine running smoothly.
* **Ignition, Starting, and Charging:** Comprehensive information on these vital systems, ensuring you have the knowledge to diagnose and repair any issues.
* **Auto Transmission and Clutch:** Detailed instructions for servicing and repairing automatic transmissions and clutches.
* **Manual Transmission:** Comprehensive instructions for manual transmissions.
* **Transfer, Propeller, and Drive Shaft:** Covers these essential components for optimal drivetrain performance.
* **Differential and Axle Suspension:** Complete information on these systems, essential for a smooth and safe ride.
* **Tire and Wheel:** Guidance on tire maintenance, repairs, and proper wheel selection.
* **Brake Control:** Detailed instructions for maintaining and repairing brake systems, ensuring safety on the road.
* **Brakes and Parking Brake:** Covers all aspects of brake systems, including calipers, rotors, and parking brake operation.
* **Steering Column and Power Steering:** Comprehensive information on steering systems, ensuring safe and responsive handling.
* **Air Conditioning:** Detailed instructions for maintaining and repairing your air conditioning system.
* **Supplemental Restraint System (SRS):** Information on the SRS system, including seatbelts and airbags.
* **Engine Immobilizer:** Covers the operation and troubleshooting of the engine immobilizer system.
* **Cruise Control:** Provides guidance on maintaining and troubleshooting your cruise control system.
* **Wiper and Washer:** Details on wiper and washer systems to ensure optimal visibility.
* **Door Lock:** Information on door locks and mechanisms.
* **Meter, Audio/Visual Systems, and Horn:** Covers the dashboard instruments, audio systems, and horn.
* **Windshield, Glass, Mirrors, and Instrument Panel:** Instructions for replacing and repairing these components.
* **Seats:** Covers seat mechanisms, adjustments, and repairs.
* **Engine Hood and Doors:** Provides information on these components, including their operation and repairs.
* **Exterior and Interior:** Includes instructions on maintaining and repairing the exterior and interior of your car.
* **Electrical System:** Comprehensive information on the electrical system, including wiring diagrams and troubleshooting guides.
* **Multiplex/CAN Communication:** Explains the complex electrical communication systems in your car.

This comprehensive manual empowers you to maintain and repair your Mercedes W126 SEC with confidence, saving you time and money.

The 1979-1992 Mercedes-Benz W126 SEC, often referred to simply as the SEC, is a luxurious and powerful coupe that epitomized the brand's engineering prowess and opulent design during its production run. Based on the W126 S-Class platform, the SEC, which stands for "S-Klasse, Einspritz-Coupé," introduced a refined and sporty alternative to the traditional sedan, catering to discerning drivers seeking a blend of comfort, performance, and exclusivity. Its sleek, timeless design, characterized by sharp lines, a long hood, and a graceful sloping roofline, remains captivating even today, highlighting its enduring appeal.

The SEC was available with a range of powerful engines, including the legendary 5.0L and 5.6L V8s, as well as a potent 5.0L V8 with fuel injection. These engines delivered impressive acceleration and a smooth, refined driving experience, coupled with the robust build quality and impeccable craftsmanship synonymous with Mercedes-Benz. The SEC's advanced chassis, featuring independent suspension at all four corners and powerful brakes, provided exceptional handling and stability, making it a joy to drive on both winding roads and long journeys. The interior of the SEC, reflecting the brand's commitment to luxury, featured high-quality materials, meticulously crafted seats, and an array of advanced features for the time, including climate control, power windows, and an optional sunroof. The SEC's combination of performance, luxury, and enduring appeal cemented its place as a coveted classic, making it a sought-after vehicle for discerning collectors and enthusiasts alike.