Safety Functions

Safety Functions
Manually Engaged Downshifts
Manual downshifts are not carried out at excessively high speeds. At a vehicle speed above approx. 5 mph (8 km/h), the reverse lock prevents reverse gear being shifted hydraulically.

On-Board Diagnostics
By way of plausibility checks and checking the line connections for shorts or breaks, the control unit can detect and store defects.

Mechanical Emergency Program
In the event of failure of the transmission valve body control or when defects are detected which lead to critical driving situations (e.g.: impermissible downshifts), the mechanical emergency program is activated. Power supply to the solenoid valves in the transmission control unit is switched off (emergency program) and the failure display activated. The main pressure assumes its maximum value and the reverse lock and P/N shift-lock, if installed, of the selector lever are not active.

EGS Control System Failure
In the event of failure of the control unit, the power supply to the solenoid valves is cut (emergency program).

Engine Overrev Protection
To ensure the engine cannot be overrevved by downshifting during a control unit failure, the transmission shifts to 4th gear (emergency program) while driving. After restarting the engine, a hydraulic forced gearshift function ensures the vehicle drives in 3rd gear (emergency program).