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 communcation lines for normal ESP control, and sets this code if an ECM message is not received within 500ms.
Item
Detecting Condition
Possible cause
DTC Strategy
CAN message monitoring
Faulty ECM
Open or short in CAN communication line
Poor connection
Enable Conditions
In case that EMS1 or EMS2 message was not received for more than 500ms within normal voltage condition.
Fail Safe
Inhibit the ESP/DBC control and allow the ABS/EBD control.
The ESP/DBC warning lamp is activated.