The ABS ECU supplies battery power to the electric motor by way of a motor relay which is controlled by the Electronic Control Unit(ECU).
The electric motor pump supplies hydraulic pressure to all wheel brake calipers by operating the piston inside the pump.
The ABS ECU monitors the pump motor relay or fuse open, open or short in motor or motor lock and then sets this code if a malfunction is detected.
Item | Detecting Condition | Possible cause | |
DTC Strategy |
•
Voltage Monitoring | 1. Open or short of power supply circuit (ABS1) 2. Faulty HECU | |
Case 1 | MonitoringPeriod |
•
Continuously | |
Enable Conditions |
•
A failure is detected if supply voltage under 7.0V at the pump motor iscontinued over 300ms - Stop ABS/VDC control immediately, permit EBD control partially | ||
Case 2 | MonitoringPeriod |
•
Only for motor relay on | |
Enable Conditions |
•
A failure is detected if voltage at pump motor does not go up to over (3.0±0.5)V within 80ms after motor relay on, or voltage at the pump motor is under (battery voltage – 4.0V) for more than 500ms. - Stop ABS/VDC control immediately, permit EBD control partially | ||
Case 3 | MonitoringPeriod |
•
Only for motor relay off | |
Enable Conditions |
•
A failure is detected if voltage at pump motor is over (3.0±0.5)V for more than 2.5s - Stop the ABS/VDC control immediately when found in uncontroled status, prohibit control after finishing control when found in controlled status. | ||
Case 4 | MonitoringPeriod |
•
Only for motor relay On->Off | |
Enable Conditions |
•
ECU monitors if voltage at pump motor is on the high-Level during some time(TSL). The TSL is calculated by voltage at ECU and duty ratio function about motor operation. The duration for Low level of motor voltage should be under 40ms for TSL. Motor should be operated maximum three times when duration is over 40ms. The monitoring detect a failure if it is still over 40ms after that - Stop ABS/VDC control immediately, permit EBD control partially | ||
Fail Safe |
•
The ABS/ESP functions are inhibited.
•
The ABS/ESP warning lamps are activated. | ||
