The HECU supplies battery power to all soleonid valves with a valve relay which is controlled by the Electronic Control UNIT(ECU).
The valve relay and all solenoid valves are installed inside the HECU ( Hydraulic and Electronic Control Unit ).
ABS ECU monitors voltage of the valve relay to check if ABS ECU can perform ABS control normally.
When the valve relay is switched to ON, the HECU will set this code if the solenoid drive voltage is below permissible voltage ranges for a period of time.
When the valve relay is switched to OFF, the HECU sets this code if the solenoid drive voltage is over the permissible voltage range for a period of time.
Item | Detecting Condition | Possible cause | |
DTC Strategy |
•
Voltage Monitoring | 1. Open or short of power supply circuit 2. Faulty HECU | |
Monitoring Period | Case 1 (Open) |
•
If the valve relay is switched on and the reference voltage of valve relay < 5 ± 0.5V continuously for 56ms, the failure is detected | |
Case 2 (Short or leakage) |
•
If the valve relay is switched off and voltage of valve relay > 6 ± 0.5V or < 2.5 ± 0.5V continuously for 56ms, the failure is detected | ||
Fail Safe |
•
The ABS/EBD/ESP/DBC functions are inhibited
•
The ABS/EBD/ESP/DBC warning lamps are activated | ||
