2004 BMW 645Ci 2D Convertible, AutomaticFACTORY OEM SERVICE PROCEDURE

12 00 Contents of Engine Electrical System General

General Information -> Working on ignition system, refer to WORKING ON IGNITION SYSTEMΒ .

-> Removing and installing electronic control units, refer to REMOVING AND INSTALLING ELECTRONIC CONTROL UNITSΒ .

-> Welding work (overload protection of control units), refer to WELDING WORK (OVERLOAD PROTECTION OF CONTROL UNITS)Β .

-> Disconnecting and connecting battery, refer to DISCONNECTING AND CONNECTING BATTERYΒ .

-> Disconnecting and connecting test equipment, refer to DISCONNECTING AND CONNECTING TEST EQUIPMENTΒ .

-> Component inspection:, refer to COMPONENT INSPECTIONΒ .

-> External jump-starting aid, refer to EXTERNAL JUMP-STARTING AIDΒ .

-> Compression testing, refer to COMPRESSION TESTINGΒ .

Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.