BMW 850i E31 1991 Electrical Troubleshooting Manual

This comprehensive Electrical Troubleshooting Manual provides detailed guidance for diagnosing and repairing electrical faults in the 1991 BMW 850i E31 model.

Key Features and Benefits:

  • Step-by-step troubleshooting procedures guide you through the diagnostic process, identifying potential causes and solutions.
  • Detailed electrical schematics and diagrams visually represent the electrical systems, aiding in component identification and circuit tracing.
  • Important specifications and measurements ensure accurate and efficient repairs.
  • Tailored specifically for the 1991 BMW 850i E31, catering to its unique electrical system configuration.
  • Empowers users to perform electrical repairs themselves, saving time and money while gaining a deeper understanding of their vehicle.

Technical Specifications and Details:

Electrical System:

  • 12-volt negative ground system
  • Battery capacity: 90 Ah
  • Alternator output: 140 amps

Major Electrical Components:

  • Engine control module (ECM)
  • Ignition coil
  • Starter motor
  • Voltage regulator
  • Headlight switch
  • Turn signal switch
  • Wiper switch

Maintenance and Repair Information:

Battery Replacement:

  • Recommended battery: BMW-approved 12-volt battery with 90 Ah capacity
  • Battery location: Under the hood, on the passenger side

Fuse and Relay Replacement:

  • Fuse and relay panel locations:
    • Under the hood, next to the battery
    • Inside the cabin, under the dashboard
  • Fuse and relay identification: Refer to the electrical troubleshooting manual for specific locations and ratings

Electrical Troubleshooting:

  • Use a multimeter to measure voltage, current, and resistance
  • Inspect wiring harness for damage or loose connections
  • Consult the electrical troubleshooting manual for circuit testing procedures

Common Electrical Problems and Solutions:

Battery Drain:

  • Symptoms: Difficulty starting the vehicle, dim headlights
  • Solution: Check for parasitic drains using a multimeter, inspect battery terminals for corrosion

Electrical Shorts:

  • Symptoms: Blown fuses, intermittent electrical failures
  • Solution: Inspect wiring harness for damage, repair or replace damaged wires

Ground Faults:

  • Symptoms: Electrical components not functioning properly
  • Solution: Check ground connections for tightness and corrosion, clean or repair as needed

This comprehensive BMW 850i E31 1991 Electrical Troubleshooting Manual is an indispensable resource for owners and technicians alike. Its detailed troubleshooting procedures, electrical schematics, and technical specifications empower you to diagnose and repair electrical faults with confidence and precision.

CONTENTS

  • INDEX
  • INTRODUCTION
  • SYMBOLS
  • POWER DISTRIBUTION CHART
  • FUSE CHART
  • POWER DISTRIBUTION
  • FUSE DETAILS
  • GROUND DISTRIBUTION
  • DATA UNK
  • ENGINE CONTROL SYSTEM (DMEM1.7, 12-CYUNDER M70)
  • CHARGING SYSTEM
  • START
  • ELECTRONIC THROTTLE CONTROL (EML12-CYUNDER)
  • E-BOX FAN
  • ELECTRONIC TRANSMISSION CONTROL(EGS)
  • ELECTRIC STEERING COLUMN ADJUSTMENT
  • STEERING COLUMN MEMORY (LSM)
  • SUPPLEMENTAL RESTRAINT SYSTEM (AIRBAG)
  • POWER ASSIST STEERING (SERVOTRONIC)
  • SUP CONTROL (ABS/ASC)
  • SUP CONTROL (ABS/ASC)
  • SUP CONTROL (ABS/ASC + T)
  • TIRE PRESSURE CONTROL (RDC)
  • ELECTRONIC SHOCK ABSORBERCONTROUII+ (EDCIII + )
  • POWER MIRRORS
  • ZKE DOOR LOCK HEATING (TSH)
  • ZKE CENTRAL LOCKING (ZV)
  • ZKE POWER WINDOWS (FH)
  • POWER SUN SHADES
  • POWER SEATS
  • SEAT/MIRROR MEMORY SYSTEM (SM/SPM)
  • HEATED SEATS
  • ZKE SUNROOF (SHD)
  • CENTRAL BODY ELECTRONICS (ZKE II)
  • HORN
  • WIPER/WASHER CONTROL
  • WINDSHIELD WIPER PRESSURE CONTROL (ADV)
  • HEADUGHT WASHER (SRA)
  • WINDSHIELD WASHER JET HEATERS
  • BODY ELECTRONICS MODULE (EKM)
  • INSTRUMENT CLUSTER

Language: English
Format: PDF
Pages: 427

BMW 850i E31 1991 Electrical Troubleshooting Manual