Purpose Of The System
The EML IIIs is an electronic throttle control system for the M73 V-12 engine. The EML IIIs was designed and developed by Siemens to BMW specifications.
The EML IIIs system uses two throttle valves and one pedal position sensor (PWG). The EML IIIs control module regulates the position of the throttle valves based on the input from the pedal position sensor.
In addition to throttle control, the main functions of the EML IIIs include:
- Idle stabilization by regulating the throttle openings at idle.
- Throttle valve positioning for optimum starting.
- Synchronization of the cylinder banks.
- Air volume control for ASC/DSC operation.
- Cruise control regulation (the EML IIIs control module contains the GR II logic introduced on the E38 740).
- Maximum road speed limiting
The operation of the EML IIIs is enhanced with additional backup (redundancy) features. This helps ensure reliable operation while maintaining a high level of operational safety.
The fault memory of the EML IIIs control module is stored in an EEPROM so that disconnection of the battery will not erase any stored faults.
The EML IIIs system is incorporated into the driving management system and is connected to the CAN line for signal interfacing with the ECM, ASC+T and AGS control modules.
The EML IIIs system includes:
- The EML IIIs control module contains two separate processors for redundant checking of inputs and output controls.
- Each throttle valve is controlled by two separate stepper motors driving one rotor
- The external safety path.
- E38 EML fault indication is handled by the Check Control Module, through the instrument cluster matrix display.
- The hall sensor brake pedal switch is used for the brake pedal input.
- Logic monitoring of pedal/throttle valve operation