Vehicle Market Segment:
Luxury Grand Tourer (GT), a halo car for BMW during its production era.
Vehicle Usp:
Known for its striking coupe styling, V12 engine, and advanced technology for its time.
Primary Competitors:
Porsche 928, Mercedes-Benz SL (R129), Jaguar XJS, Aston Martin DB7.
Manual Value Proposition:
Empowers owners and independent repair shops to perform complex electrical diagnostics and repairs, saving significant costs on dealership labor.
Ease Of Use:
Designed for ease of use with clear diagrams and step-by-step instructions, suitable for various skill levels.
Accessibility:
Instant download provides immediate access to critical repair information, eliminating shipping delays and costs.
Systems Covered:
Full Vehicle Electrical System, Engine Management, Fuel System, Ignition System, Transmission Control, ABS/Traction Control, Climate Control, Lighting, Instrumentation, Power Accessories, Body Control Modules, Audio System, Security System, Diagnostic Connectors and Circuits.
Estimated Page Count:
Extensive (typical for comprehensive wiring diagrams, often 100+ pages)
Manual Type:
Wiring Diagram Manual / Electrical Troubleshooting Manual
Powertrain Electrical:
Detailed schematics for the M70 V12 engine, including ignition, fuel injection (DME), EML (throttle control), and sensors.
Chassis Electrical:
Comprehensive coverage of ABS, ASC+T (Automatic Stability Control + Traction), EDC (Electronic Damper Control).
Comfort Convenience:
Wiring for power seats, windows, mirrors, sunroof, central locking, remote keyless entry, and climate control systems.
Lighting Instrumentation:
Headlights (including Xenon options where applicable), taillights, interior lighting, dashboard illumination, and warning lights.
Audio Telematics:
Wiring for the factory radio, amplifier, speaker systems, and early telematics/navigation components.
Troubleshooting Methodology:
Includes guidance on systematic troubleshooting using wiring diagrams, identifying common fault points.
Component Identification:
Clear identification of electrical components, connectors, fuses, and relays with their respective pin assignments.
Wiring Repair:
Guidance on diagnosing and repairing broken wires, damaged connectors, and faulty grounds.
Diagnostic Port Usage:
Information on accessing diagnostic codes through the OBD-I port (pre-OBD-II) and understanding the signals.
Depth Of Coverage:
Detailed component-level and circuit-level schematics, offering an in-depth understanding of the vehicle's electrical architecture.
Diagnostic Focus:
Primarily focused on electrical diagnostics and troubleshooting, essential for identifying and rectifying electrical faults.
Searchability:
Typically searchable PDF for quick access to specific terms and components.
Printability:
All pages are printable, allowing for physical copies for workshop use.
Binding Type Recommendation:
N/A (Digital Download)
Paper Type Recommendation:
N/A (Digital Download)
Operating Systems:
Compatible with all versions of Windows and macOS.
Software Requirements:
Adobe Acrobat Reader or compatible PDF viewer.
Engine Type:
Naturally Aspirated V12
Displacement:
4.988 L (304.4 cu in)
Bore X Stroke:
84.0 mm x 90.0 mm (3.31 in x 3.54 in)
Horsepower:
296 hp (221 kW) at 5200 rpm
Torque:
332 lb-ft (450 Nm) at 3900 rpm
Fuel Delivery:
Sequential Multi-Point Fuel Injection (Bosch Motronic M1.2 or M1.3 depending on specific year/market)
Fuel Type:
Unleaded Premium Gasoline (91+ RON)
Standard Transmission Type:
4-speed Automatic (ZF 4HP-24)
Optional Transmission Type:
6-speed Manual (Getrag S6S 420G) - Less common, highly sought after by enthusiasts.
Transmission Features:
Electronic control for automatic transmission, driver-selectable modes (e.g., Sport/Economy) on some models.
Automatic Transmission Fluid:
Typically Dexron-III or equivalent (refer to manual for exact spec)
Crash Test Data Availability:
Limited official crash test data from era, but designed with advanced safety structures for its time.
Active Safety Systems:
Anti-lock Braking System (ABS), optional ASC+T (Automatic Stability Control + Traction).
Passive Safety Features:
Driver and front passenger airbags, crumple zones, reinforced passenger cell, three-point seatbelts with pretensioners.
Infotainment System:
Factory fitted BMW Professional RDS stereo system with cassette player, optional CD changer. Early navigation system options available.
Driver Assistance Features:
ABS, ASC+T, EDC (Electronic Damper Control) offering adaptive damping based on road conditions and driving style.
Connectivity Features:
Limited by modern standards; primarily focused on in-car audio and basic communication features if equipped with early telematics.
Oil Change Interval:
Typically every 7,500-10,000 miles or 12 months, depending on driving conditions (refer to owner's manual for specific recommendation).
Major Service Intervals:
Spark plug replacement, coolant flush, brake fluid flush typically recommended around 30,000-60,000 miles.
Engine Oil Specification:
BMW Longlife-98 (or equivalent high-quality synthetic 5W-30 or 5W-40, consult manual)
Coolant Specification:
BMW blue coolant (G48 ethylene glycol based) or equivalent.
Brake Fluid Specification:
DOT 4 High Performance.
Common Electrical Issues:
ABS/ASC control module failures, headlight motor failures, VANOS system issues (on later variants), fuel pump relay failures, door lock actuator issues, window regulator problems, aging wiring harness insulation.
Common Mechanical Issues:
Cooling system leaks (radiator, hoses), oil leaks from V12 engine seals, ignition coil issues, early VANOS solenoid failures.
Bmw Design Philosophy:
BMW's history of building performance-oriented luxury vehicles with advanced engineering.
E31 Development:
Developed as BMW's flagship coupe, intended to compete with top-tier GT cars. Featured a sophisticated multi-link rear suspension and advanced aerodynamics.
V12 Introduction:
The E31 850i was BMW's first production V12 engine car, showcasing their engineering prowess and ambition.
Production Period:
1989-1999 (with 850i specifically 1991-1995)
Production Locations:
Dingolfing, Germany.
Design Awards Mention:
The E31 8 Series was widely praised for its elegant and timeless design, often cited in automotive design critiques.
Owner Satisfaction Trends:
While initial sales were moderate due to price, later models and enthusiast ownership often highlight build quality and driving experience, though maintenance costs can impact satisfaction.
Manual Certification:
N/A (Commercial Product)
