🏷️ Basic Information Identification Make: BMW Model: 850i Chassis Code: E31 Generation Production Years: 1989-1999 Specific Model Years Covered: 1991-1992 Codes Engine Code Indicator: M70 Chassis Code Indicator: E31 👋 Introduction Market Position Vehicle Class: Luxury Grand Tourer (GT), Personal Luxury Coupe. Target Audience: Affluent individuals seeking a high-performance, luxurious, and technologically advanced vehicle. Competitive Analysis Key Competitors: Mercedes-Benz SL-Class (R129), Porsche 928, Jaguar XJ-S. Key Features Design Philosophy: Elegant, timeless design with a focus on aerodynamics and driver comfort. A departure from BMW's traditional sporting sedans. Powertrain Emphasis: Powerful V12 engine providing smooth, effortless acceleration suitable for long-distance touring. Manual Value Proposition Purpose For Owner: Empowers owners and independent technicians to diagnose and repair complex electrical issues efficiently, reducing reliance on dealership service. 📋 Manual Details Coverage Areas Primary Focus: Electrical Systems Troubleshooting Included Systems: Power Distribution, Fuses, Grounds, Data Link, Engine Control, Charging, Starting, Transmission Control, SRS, ABS, Power Mirrors, Central Locking, Power Windows, Power Seats, Heated Seats, Sunroof, Horn, Wiper/Washer, Headlight Washer, Instrument Cluster, Clock, Lighting, Crash Control, Climate Control, Audio Systems, Telephone, Cruise Control, Anti-Theft, On-Board Computer Page Count Estimated Pages: Varies by edition, typically 300-600 pages for comprehensive electrical troubleshooting manuals. Manual Type Type: Electrical Troubleshooting Manual / Wiring Diagram Manual Language Language: English (assumed based on product name, OEM manuals may also exist in German and other languages) Format Format: Digital (PDF) or Printed (likely intended for digital sale) 📖 Manual Coverage Systems Covered Power Management: Detailed charts and explanations for power distribution and fuse layouts. Engine And Powertrain Electronics: Engine Control System (DME), Electronic Transmission Control (EGS), Charging System, Starting System. Chassis And Safety Electronics: Slip Control ABS (Anti-lock Braking System), Supplemental Restraint System (SRS/Airbag), Crash Control Module. Comfort And Convenience Electronics: Power Mirrors, Central Locking, Power Windows, Power Seats, Heated Seats, Power Sun Roof, Horn, Wiper/Washer Systems, Headlight Washer, Windshield Washer Jet Heaters. Instrumentation And Information: Instrument Cluster, Multi-Function Clock, On-Board Computer. Lighting Systems: Light Switch Details, Headlights/Fog Lights, Turn/Hazard Lights, Park/Tail/Underhood Lights, License Plate/Luggage Compartment Lights, Back-up Lights, Brake Lights, Interior Lights, Glove Box/Ashtray Lights, Charging Socket. Climate Control And Audio: Park Ventilation with HKR (Heated Seats/Rear Window Defogger), Rear Window Defogger, Integrated Climate Regulation, Radio/CD Player, Radio/Hi-Fi, Cellular Telephone. Driver Aids And Security: Cruise Control (Tempomat), Anti-Theft System. Procedures Included Troubleshooting Methodology: Step-by-step diagnostic procedures for electrical faults, circuit analysis. Component Identification: Component Location Charts and Views to identify module and connector positions. Wiring Diagrams: Detailed wiring schematics for all covered electrical systems, including connector views and splice locations. Fuse And Relay Identification: Specific fuse and relay assignments with corresponding circuit functions. Data Link Diagnosis: Information related to accessing vehicle diagnostic data via the Data Link connector. Technical Depth Depth: Advanced diagnostic and troubleshooting, focusing on electrical fault finding and repair. Assumes a foundational understanding of automotive electrical principles. 📊 Manual Specifications File Format Digital Format: PDF (Searchable text, vector graphics for diagrams highly desirable) Print Quality Diagram Clarity: High-resolution diagrams essential for accurate interpretation of wiring and component layouts. Binding Type Physical Manual Binding: If printed: Spiral-bound or perfect-bound for ease of use on a workbench. Paper Type Physical Manual Paper: If printed: Durable, matte finish paper suitable for workshop environments. ⚙️ Engine Specifications Primary Engine Engine Type: Naturally Aspirated V12 Engine Code: M70 B50 Displacement: 4.988 cc (5.0 Liters) Performance Horsepower: 296 hp @ 5,200 rpm Torque: 317 lb-ft (430 Nm) @ 3,900 rpm Fuel System Fuel Delivery: Bosch Motronic M-1.2 Electronic Fuel Injection (Dual ECUs, one per cylinder bank) Fuel Type: Premium Unleaded Gasoline (91 Octane or higher) Cooling Cooling System: Pressurized Liquid Cooling System Ignition Ignition System: Distributorless Ignition (Coil-on-plug per cylinder bank) 🔧 Transmission Standard Transmission Type: 4-speed Automatic (ZF 4HP24) Optional Manual Transmission Availability: Optional 6-speed manual transmission (Getrag 420G) was available on some E31 models, but less common for the 850i and potentially not for the 91-92 E31 850i depending on market. This manual likely covers the automatic. Features Electronic Control: Electronic Transmission Control (EGS) for adaptive shifting and diagnostics. Fluid Specifications Transmission Fluid Type: BMW ATF LT-2 or equivalent (e.g., Pentosin ATF1100) 📐 Dimensions Exterior Length: Approx. 191.1 inches (4854 mm) Width: Approx. 71.7 inches (1821 mm) Height: Approx. 52.0 inches (1321 mm) Wheelbase: Approx. 106.3 inches (2700 mm) Weights Curb Weight: Approx. 4,000-4,200 lbs (1814-1905 kg) 🛡️ Safety Features Ratings Crash Test Data: Limited official crash test data available from the period. Focus was on passive safety features. Active Features Traction Control: Automatic Stability Control (ASC) was available as an option on later models, ABS standard. Braking System: Anti-lock Braking System (ABS) standard. Passive Features Airbags: Driver's side airbag standard. Body Structure: Reinforced safety cage, crumple zones. 💡 Technology Features Infotainment Audio System: Optional high-fidelity audio systems, including BMW HiFi and potentially Harman Kardon (HKR). Cd Player: Factory fitted CD player...