The HECU is composed of a ECU (Electronic Control Unit ) and a HCU( Hydraulic Control Unit) , so the HECU hardware includes all solenoid valves inside the unit as well as the ECU.
The HECU monitors the operation of the IC components such as memory, register, A/D converter and so on. The HECU sets this code when the EEPROM data read by the master processor is different than prior data writed, or when the master/slave processor detects abnormal operation in RAM, Status Register, Interrupt, Timer, A/D converter or cycle time.
Item | Detecting Condition | Possible cause |
DTC Strategy | ● Internal monitoring | ● Faulty HECU |
Detect Mode | ● Initial Check ● Outside the ABS control cycle ● Inside the ABS control cycle ● Diagnosis mode ● Failure mode | |
Enable Conditions | ● When the MCU can’t erase or write a data of the EEPROM. ● When the master/slave processor detects abnormal operation in RAM, status register, interrupt, timer, A/D converter and cycle time. | |
Fail Safe | ● System down. The ABS/EBD/TCS/ESP functions are inhibited. - The valve relay and all solenoids are prevented from being switched on. ● The ABS/EBD/TCS/ESP warning lamps are activated. |
