Abs Circuit In Each Operation Range - SSANGYONG Kyron Repair Manual

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5. ABS CIRCUIT IN EACH OPERATION RANGE

1
Low pressure
chamber
Pump
Hydraulic Pressure Circuit when ABS is Not Operating
The hydraulic pressure in the master cylinder increases
through the vacuum booster and it is delivered to the wheel
via the normal open inlet valve. At this moment, the nor-
mally-closed outlet valve is closed. The speed of the wheel
that hydraulic pressure is delivered reduces gradually.
3
Low pressure
chamber
Pump
Inlet valve
Pressure Decreases in the Circuit when ABS is Operating
Even when the hydraulic pressure on each circuit is stable,
the wheel can be locked as the wheel speed decreases.
This is when the ABS ECU detects the wheel speed and
the vehicle speed and gives the optimized braking without
locking the wheels. In order to prevent from hydraulic pres-
sure increases, the inlet valve is closed and the outlet valve
is opened. Also, the oil is sent to the low pressure cham-
ber and the wheel speed increases again. The ABS ECU
operates the pump to circulate the oil in the low pressure
chamber to the master cylinder. This may make the driver
to feel the brake pedal vibration and some noises.
ABS/ESP SYSTEM
KYRON SM - 2005.09
Inlet valve
Outlet valve
Outlet valve
2
Low pressure
chamber
Pump
No Hydraulic Pressure Circuit when ABS is Operating
As hydraulic pressure on each wheel increases, the wheel
tends to lock. In order to prevent the wheel from locking, the
hydraulic valve modulator operates the inlet valve control
solenoid to close the inlet valve and stop the hydraulic pres-
sure increases. At this moment, the outlet valve is closed.
This procedure helps the wheel to maintain a stable hy-
draulic pressure.
4
Low
pressure
chamber
Pump
Pressure Increases in the Circuit when ABS is Operating
As the wheel speed increases, the inlet valve opens and
the wheel's pressure increases due to the master cylinder
pressure. The oil in the low pressure chamber circulates
to the wheel by the pump and the wheel speed decreases
as the hydraulic pressure at wheel increases. This opera-
tion continues repetitively until there are no signs that the
ABS ECU is locking the wheels. When the ABS hydraulic
pressure control takes place, there may be some vibration
and noises at the brake pedal.
Inlet valve
Outlet valve
Inlet valve
Outlet valve
CHANGED BY
EFFECTIVE DATE
AFFECTED VIN