Electronic Transmission Control (EGS/AGS)

Electronic Transmission Control (EGS/AGS)

BMW uses two different automatic transmissions one manufactured by ZF, the other manufactured by Hydramatic. The electronic control for the transmissions is produced for BMW by Bosch.

ZF transmissions include: 4HP 22/24 EH
A 5 S 310 Z (5HP 18)
A 5 S 560 Z (5HP 30)

Hydramatic transmission: A 4 S 310 R

Functions of EGS/AGS include: Shift Control
Pressure Control
Converter Lock Up Control

The system control module monitors the transmission input signals, processes the input data and electronically activates the transmission's hydraulic components. Like DME, the transmission control module monitors the system for correct function.

When a fault occurs that affects the control modules ability to monitor or activate a component, it activates a warning lamp or posts a message in the Check Control matrix display which indicates a fault.

The examples below show the Check Control message and the E36 Transmission indicator in the instrument cluster.












Electronic Transmission Control













All BMW automatic transmissions are electronically controlled.

Each control system has an identification number as follows:
The electronics control the hydraulic functions of the transmission. Electronic control provides smoother shifts, improved fuel economy, longer service life, and availability of different shift patterns based on driving mode.

Some of the electronic control systems are self learning (adaptive). The adaptive electronic control system monitors wheel slip and driving style of the driver. If required, it automatically changes the shift patterns to provide sporty, economical or winter shifting programs to suit the driver and the road conditions.

The electronic control systems are called EGS and AGS. These are German acronyms for Electronishe Getriebesteurung and Adaptiv Getriebesteurung. Translated to English this means Electronic Transmission Control and Adaptive Transmission control respectfully.

Transmission Control System Identification








The transmission control system is identified by electronic display on the DIS tester and by a visual check of the control module.