The HECU sends requirement data, such as torque reduction, the number of fuel cut cylinders, and the ESP control request, to the ECM through CAN bus line. The ECM performs the fuel cut function according to a request signal from the HECU and then retards an ignition timing. The ECM maintains current gear position during the ESP control period in order not to increase power which causes a Kickdown shift.

The HECU checks the CAN communcation lines for the normal ESP control, and sets this code if the data received from EMS is not the same with that from TCM.