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 in power supply circuit (IGN+) | |
Case 1 | MonitoringPeriod |
•
Continuously | |
Enable Conditions |
•
A fault is detected if the supply voltage of valve relay is under (battery voltage – 4.0V) over 500ms after valve relay on. | ||
Case2 | MonitoringPeriod |
•
Performe once during initialization after ignition on | |
Enable Conditions |
•
A Fault is detected if valve relay voltage does not go up to 80% of battery voltage for a time 60ms after valve relay on. | ||
Fail Safe |
•
The ABS/EBD/ESP functions are inhibited.
•
The ABS/EBD/ESP warning lamps are activated. | ||
Case 3 | MonitoringPeriod |
•
Performe once during initialization after ignition on | |
Enable Conditions |
•
A Fault is detected if valve relay voltage does not come to under 80% of battery voltage within 60ms after valve relay is changed off form on. | ||
Fail Safe |
•
The ABS/ESP functions are inhibited.
•
The ABS/ESP warning lamps are activated. | ||
