Synchronization After Replacing DME Control Unit

The following information is important when replacing one or both DME control units.

- Each electronic control unit is programmed with certain basic values, which are only mean values.
- A control unit, however, receives variable input values depending on the vehicle operating conditions, which are permanently compared with the stored values. The adaptive system first compares them, then determines corrective values required for a pertinent operating condition and finally forwards the latter values to the concerned components such as air volume meters, throttle valve assemblies, Motronic control units and so on.
- If, for example, the Motronic control units were without current for a long period of time (more than 1 hour), its adaptive system would lose the stored values.
- The adaptive system would have to find a balanced level between the programmed values and engine-oriented operating condition values after restoring operation of an erased control unit or installing a new control unit.

- Consequently there must be conformance with the following procedures before an EML or DME control unit is replaced or after restoring operation of a disconnected control unit.

- Run engine to operating temperature.
- Install new control unit and drive car, whereby the car must coast three times from speeds above 5,000 rpm to the idling range in transmission range 1 (approx. 10 seconds).
- Have engine run at idling speed in transmission range P or N at least 5 minutes.

- These procedures serve immediate and precise synchronization of both banks of cylinders in all operating conditions.