1. HECU
The HECU sends requirement data, such as torque reduction, the number of fuel cut cylinders, and the ESP control request, to the PCM(ECM & TCM) through CAN bus line. The PCM(ECM) performs the fuel cut function according to a request signal from the HECU and then retards an ignition timing. The PCM(TCM) 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 communication lines for normal ESP control, and sets this code if CAN BUS OFF status is detected.
Item
Detecting Condition
Possible cause
DTC Strategy
Open or short circuit monitoring
Open or short circuit in CAN line
Faulty HECU
Enable Conditions
Monitoring a fault in case of Bus off on CAN line after IGN on
Fail Safe
Inhibit the ESP control and allow the ABS/EBD control
The ESP warning lamp is activated