The Active Corner Enhancement system manufactured by Rover Group Lucas appears to have been produced specifically for the Land Rover Discovery series II to address the poor cornering association of the Discovery series one. Constantly monitoring very sensitive G sensors mounted at high and low points on the vehicle, the system can detect roll forces and counter them using the output of a hydraulic pump via valves and powerful actuators mounted on both axles to resist the roll forces thus reducing cornering roll. The system is a vast improvement to the vehicles handling allowing much sharper cornering than without, and anyone used to driving with is needs to be careful should it stop working, or due to the fact that it was an optional extra, they lend a non ACE equipped vehicle, not to forget to slow down more than usual at corners. The system has very fast response requirements and as such there is much emphasis on ensuring that the system works properly and fast enough. New ECUs have to pass a number of response tests successfully before the system is commissioned to try and ensure this. There is also sensor calibration and sophisticated bleeding procedures.

Interestingly or amusingly, the ECU is housed in an identical case to the MEMS 1.9 engine management with a blanking plug fitted where the vacuum tube inlet is, no doubt a cost saving measure.