BMW 7 Series: Notes/Information On Removing And Installing Control Units

IMPORTANT:

• Disconnecting the vehicle battery will cancel the fault memories of control units. Consequently, before disconnecting the car's battery, always interrogate the fault memories. Investigate stored faults and, once any faults have been remedied, cancel the fault memory.
• Control unit plugs should only ever be connected and disconnected while the ignition is turned off.
• The removal and installation of components, relays, fuses etc. can cause faults to be stored in fault memories capable of self diagnosis. Always interrogate the fault memories after completing work on the electrical system.
• Investigate stored faults and, once any faults have been remedied, cancel the fault memory.
• If necessary, initialize power window units
  When replacing the DME/DDE control unit, observe the following:
• In each case read out the hardware/software status of the relevant control unit using the BMW diagnosis system.

  Comply with the instructions of the DIS diagnosis system on the steps pertaining to coding and programming.

  On vehicles with electronic vehicle immobilization, comply with the instructions of the BMW diagnosis system.

• Each control unit is programmed with certain basic values, which serve as mean values. The control unit receives different input values, depending on engine condition, which are compared with the stored values. The adaptive system compares the input values with the stored map values. The control commands are routed to the relevant actuators.
• If the DME control unit is without current for a long time (more than one hour), its adaptive system loses the stored values. When a cleared control unit is restarted or a new control unit is installed, the adaptive system must read in and store the input values of the associated engine as new basic values itself.
• This procedure could lead to erratic idling and disturbed overrunning of the engine after starting. Depending on the engine it could require some time before all values are adapted to the engine condition.
• Therefore observe the following procedure before replacing or reinstalling a DME/DDE control unit:

1. If possible before exchanging control unit, run engine up to operating temperature.

2. Exchange control units and run the vehicle at alternating engine speeds.

NOTES/INFORMATION ON START ASSISTANCE (JUMP STARTING)

Do not start the engine with help of starting sprays.

Preparation

Conform with the following when starting the engine with a jump starting cable.

• Ensure that the jump starting cable wires are of appropriate cross-section size.
• Only use fuse-protected jump starting cables.
• Check whether the current-supplying battery has 12 V voltage.
• If the engine is started from the battery of another vehicle, ensure that there is no contact between the bodies of both vehicles.

IMPORTANT: Never touch electrically live ignition system components: high voltage - danger of injury!

If the battery in the vehicle supplying power is weak, start the engine of this vehicle and let it run at idling speed.

Operation

It is essential to conform to the procedures so as to avoid injury to persons or damage to parts.

• Automatic transmission: select drive position "P", apply parking brake.
• Manual transmission: move gear lever to neutral position, apply parking brake.
• Ensure that the jump leads cannot get caught in rotating parts, e.g. fan.
• First connect both positive poles of the batteries with one jump starting cable (red).
• Use the battery positive terminal in the engine compartment for vehicles with the battery in the luggage compartment.
• Then use the second jump starting cable (black) to connect the negative post of the current-supplying battery with the earth/ground point (not the negative pole or the body) of the vehicle to be started.

IMPORTANT: Do not connect the second jump starting cable (black) with the negative pole of the battery in the vehicle to be started. Produced gas could be ignited by sparks.

Risk of explosion!

After the engine of the vehicle to be started has fired, first disconnect the jump starting cable between the negative pole and the earth/ground point. Then remove the starting cable from the positive poles.

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