Engine Electrical System - Repair Instructions

• Troubleshooting
  • 12 00... Contents of Engine Electrical System General
    • General Information
  • 12 00... Information on working on ignition system
  • 12 00... Instructions for disconnecting and connecting battery
    • Notes
    • Vehicles with a two-battery system
  • 12 00... Instructions for removing and installing electronic control units
  • 12 00... Instructions for connecting and disconnecting test units
  • 12 00... Instructions on component testing
  • 12 00... Instructions on starting aid
  • 12 00... Instructions for welding work (overload protection of control units)
  • 12 13 Notes on checking ignition system
    • Troubleshooting
• Ignition Wires, Spark Plugs
  • Firing Order
  • 12 12 011 Replacing all spark plugs (N62)
• Ignition Coil
  • 12 13 Notes on checking ignition system
  • 12 13... Additional fault notes for troubleshooting
  • 12 13... Checking secondary signal for stationary ignition distribution
  • 12 13... Further fault patterns with evaluation
  • 12 13... Normal oscillogram (N42, N62)
    • Notes
    • N42 / N62:
  • 12 13... Fault in fuel injection system
  • 12 13... Spark-Plug Faults
  • 12 13... Ignition Coil Faults
  • 12 13 009 Checking rod-type ignition coils (M54, M56, N40, N42, N45, N46, N52, N62, N73)
    • Notes
    • Secondary measurement:
    • Primary measurement:
    • M54 / M56 / N40 / N42 / N45 / N46 / N62 / N73:
  • 12 13 511 Replacing ignition coil (N62)
• Electronic Switching
  • 11 37 700 Replacing control unit (Valvetronic)
  • 12 14 512 Replacing pulse generator on left exhaust camshaft (N62)
  • 12 14 513 Replacing pulse generator on right exhaust camshaft (N62)
  • 12 14 521 Replacing crankshaft pulse generator (N62)
  • 12 14 522 Replacing pulse generator on left inlet camshaft (N62)
  • 12 14 526 Replacing pulse generator on right inlet camshaft (N62)
  • 12 14 550 Replacing control unit (Digital Motor Electronics) (N62)
  • 12 14 610 Replacing right knock sensors (N62)
  • 12 14 611 Replacing left knock sensors (N62)
  • 12 14 700 Coding control module (DME / DDE)
  • 12 14 705 Programming control unit (DME / DDE)
  • 12 52 005 Removing and installing/replacing integrated supply module (N62)
  • 12 90 100 Replacing fan for electronics box (N62)
• Alternator With Drive And Mount
  • 12 31... Replacing alternator belt pulley
  • 12 31 009 Checking alternator (BSD)
    • Notes
    • Oscillogram for a fault-free alternator:
    • Oscillogram for a faulty alternator:
  • 12 31 020 Removing and installing or replacing alternator (N62)
• Starter With Mounting
  • 12 41 020 Removing and installing/replacing starter motor (N62)
  • 12 41 041 Replacing solenoid switch
• Starter Lead
  • 12 42 500 Removing and installing or replacing battery positive lead (between alternator, starter motor and battery positive terminal) (N62)
  • 12 42 540 Replacing safety battery terminal (SBK)
• Engine Wiring Loom
  • 12 51 001 Replacing wiring harness section for engine (N62)
  • 12 51 100 Replacing wiring harness section for ignition coil (N62)
• Connectors, Plugs
  • 12 52 005 Removing and installing/replacing integrated supply module (N62)
• Oil Pressure/Oil Temperature Gauge
  • 12 61 280 Removing and installing/replacing oil pressure switch (N62)
  • 12 61 285 Replacing engine oil level switch (N62)
• Control Unit Box
  • 12 90 100 Replacing fan for electronics box (N62)