BMW 3 Owners & Service Manuals

BMW 3: Engine Electrical System

Digital Motor Electronics (DME)

Digital Motor Electronics (DME)
DME 8 control unit

The Digital Motor Electronics (DME) is the computing and switching center. Sensors on the engine and the vehicle deliver the input signals and actuators implement the commands. The Digital Motor Electronics (DME) calculates the corresponding activation signals for the actuators from the input signals, and also the computing models and characteristic maps stored.

The operating voltage range of the Digital Engine Electronics (DME) is between 6 and 16 volts.

An ambient pressure sensor and a temperature sensor are integrated in the Digital Motor Electronics (DME).

The ambient pressure sensor permits precise determination of the density of the ambient air. This information is required for various diagnostic functions. In addition, in the event of a failure of the hot film air mass meter, a precise substitute value can be calculated for the cylinder filling with the help of additional input variables.

The temperature sensor measures the temperature inside the control unit. If the temperature there rises too sharply, multiple fuel injection is reduced for example, in order to cool the output stages slightly and to keep the temperature inside the control unit in a non-critical range.

The B46TU engine will have the DME 8 engine electronics generation. Depending on the engine version, the Digital Motor Electronics (DME) will be given a specific designation.

DME 8.x.y.z (x = number of cylinders, y = vehicle electric system architecture, z = H (hybrid) ) can be decoded as follows:

  • DME 8.4.0 = B46TU
  • DME 8.6.0 = B58
  • DME 8.8.0 = N63TU2

 

    READ NEXT:

    SEE MORE:

     General information

    Electronic control devices are installed in the vehicle. Electronic control units process data they receive from vehicle sensors, self-generate or exchange with each other. Some control units are necessary for the vehicle to function safely or provide assistance during driving, for instance driver

     Emergency braking function

    Regenerative braking with help of the drivetrain only effects the rear axle. The brake force on the rear axle must not exceed a specific value in proportion to that on the front axle. This would otherwise compromise driving stability. This is also why there is a limit to the maximum deceleration

    © 2019-2025 Copyright www.bmw3g20.com