Lexus RX300 (MCU15). Service manual — part 56
CH
BO
CHASSIS — BRAKES
Mode
Solenoid Valves
97
" While the Vehicle Makes a Right Turn A
VSC Activated
VSC Not
Activated
Pressure
Increase
Mode
Pressure
Holding
Mode
Pressure
Reduction
Mode
(2)
Master Cylinder Cut Solenoid Valve
(Front Right)
OFF
ON
ON
ON
(2)
Port: (A)
Open
Close
Close
Close
(3)
Master Cylinder Cut Solenoid Valve
(Fornt Right, Rear Left)
OFF
OFF
OFF
OFF
(3)
Port: (B)
Open
Open
Open
Open
(6)
Master Cylinder Cut Solenoid Valve
(Front Left, Rear Right)
OFF
ON
ON
ON
(6)
Port: (E)
Open
Close
Close
Close
(7)
Master Cylinder Cut Solenoid Valve
(Front Left)
OFF
OFF
OFF
OFF
(7)
Port: (F)
Open
Open
Open
Open
(4)
Reservoir Cut
Solenoid Valve
OFF
ON
ON
ON
(5)
Port: (C), (D)
Close
Open
Open
Open
(8)
Pressure Holding Valve
(Front)
OFF
OFF
ON
ON
(11)
Port: (G), (J)
Open
Open
Close
Close
(9)
Pressure Holding Valve
(Rear Left)
OFF
OFF
OFF
OFF
(9)
Port: (H)
Open
Open
Open
Open
(10)
Pressure Holding Valve
(Rear Right)
OFF
OFF
ON
ON
(10)
Port: (I)
Open
Open
Close
Close
(12)
Pressure Reduction Valve
(Front)
OFF
OFF
OFF
ON
(15)
Port: (K), (N)
Close
Close
Close
Open
(13)
Pressure Reduction Valve
(Rear Left)
OFF
OFF
OFF
OFF
(13)
Port: (L)
Close
Close
Close
Close
(14)
Pressure Reduction Valve
(Rear Right)
OFF
OFF
OFF
ON
(14)
Port: (M)
Close
Close
Close
Open
Front Right wheel
—
Increase
Hold
Reduction
Wheel Cylinder
Front Left wheel
—
Increase
Hold
Reduction
Wheel Cylinder
Pressure
Rear Right wheel
—
Increase
Hold
Reduction
Rear Left wheel
—
—
—
—
CHASSIS — BRAKES
98
c. Oversteer Restraining Control
In oversteer restraining control, the brake of the front and rear wheels of the outer side of the turn
is applied. As an example, the diagram below shows the hydraulic circuit in the pressure increase mode,
as it restrains an oversteer condition while the vehicle makes a right turn.
As in understeer restraining control, in other operating modes, the pressure holding valve and the pres-
sure reduction valve are turned ON/OFF according to the ABS operation pattern.
However, in oversteer control, the pressure holding valve is turned ON and blocks the hydraulic passage
to the front inner wheel in order to prevent applying the brake to the front inner wheel.
Port (A)
Port (H)
Port (G)
Port (L)
Port (K)
Port (F)
Port (I)
Port (J)
Port (M)
Port (N)
Port (B)
Port (C)
Port (D)
Port (E)
Increase Mode
161ES38
Master
Cylinder
(1)
(1)
(2)
(3)
(1)
(4)
(5)
(6)
(7)
(1)
(8)
(9)
(12)
(13)
(14)
(15)
(10)
(11)
Front Right
Wheel Cylinder
Rear Left
Wheel Cylinder
Rear Right
Wheel Cylinder
Front Left
Wheel Cylinder
Reservoirs
Pumps
" System Diagram A
187CH42
Speed Sensor
Skid
Control
ECU
Engine ECU
Brake
Actuator
Slip Indicator
Light
Stop Light
Switch
Steering Angle
Sensor
Yaw Rate
Sensor
Deceleration
Sensor
VSC Warning
Light
VSC Warning
Buzzer
CH
BO
CHASSIS — BRAKES
Mode
Solenoid Valves
99
" While the Vehicle Makes a Right Turn A
VSC Activated
VSC Not
Activated
Pressure
Increase
Mode
Pressure
Holding
Mode
Pressure
Reduction
Mode
(2)
Master Cylinder Cut Solenoid Valve
(Front Right)
OFF
OFF
OFF
OFF
(2)
Port: (A)
Open
Open
Open
Open
(3)
Master Cylinder Cut Solenoid Valve
(Front Right, Rear Left)
OFF
ON
ON
ON
(3)
Port: (B)
Open
Close
Close
Close
(6)
Master Cylinder Cut Solenoid Valve
(Front Left, Rear Right)
OFF
OFF
OFF
OFF
(6)
Port: (E)
Open
Open
Open
Open
(7)
Master Cylinder Cut Solenoid Valve
(Front Left)
OFF
ON
ON
ON
(7)
Port: (F)
Open
Close
Close
Close
(4)
Reservoir Cut
Solenoid Valve
OFF
ON
ON
ON
(5)
Port: (C), (D)
Close
Open
Open
Open
(8)
Pressure Holding Valve
(Front Right)
OFF
ON
ON
ON
(8)
Port: (G)
Open
Close
Close
Close
(11)
Pressure Holding Valve
(Front Left)
OFF
OFF
ON
ON
(11)
Port: (J)
Open
Open
Close
Close
(9)
Pressure Holding Valve
(Rear Left)
OFF
OFF
ON
ON
(9)
Port: (H)
Open
Open
Close
Close
(10)
Pressure Holding Valve
(Rear Right)
OFF
OFF
OFF
OFF
(10)
Port: (I)
Open
Open
Open
Open
(12)
Pressure Reduction Valve
(Front Right)
OFF
OFF
OFF
OFF
(12)
Port: (K)
Close
Close
Close
Close
(13)
Pressure Reduction Valve
(Rear Left)
OFF
OFF
OFF
ON
(13)
Port: (L)
Close
Close
Close
Open
(14)
Pressure Reduction Valve
(Rear Right)
OFF
OFF
OFF
OFF
(14)
Port: (M)
Close
Close
Close
Close
(15)
Pressure Reduction Valve
(Front Left)
OFF
OFF
OFF
ON
(15)
Port: (N)
Close
Close
Close
Open
Front Right wheel
—
—
—
—
Wheel Cylinder
Front Left wheel
—
Increase
Hold
Reduction
Wheel Cylinder
Pressure
Rear Right wheel
—
—
—
—
Rear Left wheel
—
Increase
Hold
Reduction
CHASSIS — BRAKES
100
6) Brake Assist Operation
The fluid pressure that has been generated by the pump in the brake actuator is directed to the wheel
cylinders. By applying a greater fluid pressure than the master cylinder, a greater braking force is achieved.
Port (A)
Port (H)
Port (G)
Port (L)
Port (K)
Port (F)
Port (I)
Port (J)
Port (M)
Port (N)
Port (B)
Port (C)
Port (D)
Port (E)
187CH21
Master
Cylinder
(1)
(1)
(2)
(3)
(1)
(4)
(5)
(6)
(7)
(1)
(8)
(9)
(12)
(13)
(14)
(15)
(10)
(11)
Front Right
Wheel Cylinder
Rear Left
Wheel Cylinder
Rear Right
Wheel Cylinder
Front Left
Wheel Cylinder
Reservoirs
Pumps
" System Diagram A
187CH43
Speed Sensor
Skid
Control
ECU
Brake
Actuator
Stop Light
Switch
ABS Warning
Light
Master Cylinder
Pressure Sensor
Нет комментариевНе стесняйтесь поделиться с нами вашим ценным мнением.
Текст