The HECU send requirement data, such as Torque reduction, the number of fuel cut cylinders, and ESP(ESC) control requests, to the Engine PCM(ECM & TCM) through CAN bus line.

The Engine PCM(ECM) performs fuel cut functions according to requests from the HECU and retards ignition timing by torque reduction requests.

The PCM(TCM) maintains current gear positions during ESP(ESC) control time, in order not to increase power which causes a Kickdown shift.