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System Description
 
 
SYSTEM DIAGRAM
 
 
INPUT SIGNAL AND OUTPUT SIGNAL
Major signal transaxle between each unit via communication lines is shown in the following table.
Component partsSignal description
ABS actuator and electric unit (control unit)ABS Actuator and Electric Unit (Control Unit)
Front LH wheel sensorWheel Sensor and Sensor Rotor
Front RH wheel sensorWheel Sensor and Sensor Rotor
Rear LH wheel sensorWheel Sensor and Sensor Rotor
Rear RH wheel sensorWheel Sensor and Sensor Rotor
Parking brake switchParking Brake Switch
Parking brake actuator (LH)Parking Brake Actuator
Parking brake actuator (RH)Parking Brake Actuator
ECMMainly transmits the following signals to ABS actuator and electric unit (control unit) via CAN communication.
  • Accelerator pedal position signal
  • Engine speed signal
  • Engine torque signal
TCMMainly transmits the following signals to ABS actuator and electric unit (control unit) via CAN communication.
  • Current gear position signal
  • CVT accept permission signal
  • Shift position signal
BCMMainly transmits the following signals to ABS actuator and electric unit (control unit) via CAN communication.
  • Stop light switch signal
Mainly receives the following signals from ABS actuator and electric unit (control unit) via CAN communication.
  • Stop light request signal
IPDM E/RMainly transmits the following signals to ABS actuator and electric unit (control unit) via CAN communication.
  • Electric motor switch ON signal
Chassis control moduleMainly transmits the following signals to ABS actuator and electric unit (control unit) via CAN communication.
  • Active ride control signal
  • Automatic brake hold operation request signal
  • Automatic brake hold release request signal
  • Chassis control module malfunction signal
  • Electric parking brake operation request signal
  • Intelligent trace control signal
Steering angle sensorMainly transmits the following signals to ABS actuator and electric unit (control unit) via CAN communication.
  • Steering angle sensor signal
Combination meterMainly transmits the following signals to ABS actuator and electric unit (control unit) via CAN communication.
  • Brake fluid level switch signal
Mainly receives the following signals from ABS actuator and electric unit (control unit) via CAN communication.
  • ABS warning light signal
  • Brake warning light signal
  • Electric parking brake indicator light signal
  • Electric parking brake warning light signal
  • ASC OFF indicator light signal
  • ASC warning light signal
  • Malfunction indicator light (MIL) signal
 
 
VALVE OPERATION [ASC FUNCTION, TCS FUNCTION, BRAKE LIMITED SLIP DIFFERENTIAL (BLSD) FUNCTION, BRAKE ASSIST FUNCTION, BRAKE FORCE DISTRIBUTION FUNCTION, hill start assist FUNCTION
Each valve is operated and fluid pressure of brake is controlled.
 
 
ASC Function, TCS Function, Brake Limited Slip Differential (BLSD) Function, Brake Assist Function, Brake force distribution Function, and hill start assist Function are in Operation (During Pressure Increases)
Component partsNot activatedWhen pressure increases
Cut valve 1Power supply is not supplied (open)Power supply is supplied (close)
Cut valve 2Power supply is not supplied (open)Power supply is supplied (close)
Suction valve 1Power supply is not supplied (close)Power supply is supplied (open)
Suction valve 2Power supply is not supplied (close)Power supply is supplied (open)
ABS IN valvePower supply is not supplied (open)Power supply is not supplied (open)
ABS OUT valvePower supply is not supplied (close)Power supply is not supplied (close)
Each brake (fluid pressure)Pressure increases
During pressure front RH brake increases
  • Brake fluid is conveyed to the pump from the master cylinder through suction valve 1 and is pressurized by the pump operation. The pressurized brake fluid is supplied to the front RH brake through the ABS IN valve. For the left brake, brake fluid pressure is maintained because the pressurization is unnecessary. The pressurization for the left brake is controlled separately from the right brake.
During pressure front LH brake increases
  • Brake fluid is conveyed to the pump from the master cylinder through suction valve 2 and is pressurized by the pump operation. The pressurized brake fluid is supplied to the front LH brake through the ABS IN valve. For the right brake, brake fluid pressure is maintained because the pressurization is unnecessary. The pressurization for the right brake is controlled separately from the left brake.
During pressure rear RH brake increases
  • Brake fluid is conveyed to the pump from the master cylinder through suction valve 2 and is pressurized by the pump operation. The pressurized brake fluid is supplied to the rear RH brake through the ABS IN valve. For the left brake, brake fluid pressure is maintained because the pressurization is unnecessary. The pressurization for the left brake is controlled separately from the right brake.
During pressure rear LH brake increases
  • Brake fluid is conveyed to the pump from the master cylinder through suction valve 1 and is pressurized by the pump operation. The pressurized brake fluid is supplied to the rear LH brake through the ABS IN valve. For the right brake, brake fluid pressure is maintained because the pressurization is unnecessary. The pressurization for the right brake is controlled separately from the left brake.
 
 
ASC Function, TCS Function, Brake Limited Slip Differential (BLSD) Function, Brake Assist Function, Brake force distribution Function, and hill start assist Function are in Operation (During Pressure Holds)
Component partsNot activatedWhen pressure holds
Cut valve 1Power supply is not supplied (open)Power supply is supplied (close)
Cut valve 2Power supply is not supplied (open)Power supply is supplied (close)
Suction valve 1Power supply is not supplied (close)Power supply is not supplied (close)
Suction valve 2Power supply is not supplied (close)Power supply is not supplied (close)
ABS IN valvePower supply is not supplied (open)Power supply is not supplied (open)
ABS OUT valvePower supply is not supplied (close)Power supply is not supplied (close)
Each brake (fluid pressure)Pressure holds
During pressure front RH brake holds
  • Since the cut valve 1 and the suction valve 1 are closed, the front RH brake, master cylinder, and reservoir are blocked. This maintains fluid pressure applied on the front RH brake. The pressurization for the left brake is controlled separately from the right brake.
During pressure front LH brake holds
  • Since the cut valve 2 and the suction valve 2 are closed, the front LH brake, master cylinder, and reservoir are blocked. This maintains fluid pressure applied on the front LH brake. The pressurization for the right brake is controlled separately from the left brake.
During pressure rear RH brake holds
  • Since the cut valve 2 and the suction valve 2 are closed, the rear RH brake, master cylinder, and reservoir are blocked. This maintains fluid pressure applied on the rear RH brake. The pressurization for the left brake is controlled separately from the right brake.
During pressure rear LH brake holds
  • Since the cut valve 1 and the suction valve 1 are closed, the rear LH brake, master cylinder, and reservoir are blocked. This maintains fluid pressure applied on the rear LH brake. The pressurization for the right brake is controlled separately from the left brake.
 
 
ASC Function, TCS Function, Brake Limited Slip Differential (BLSD) Function, Brake Assist Function, Brake force distribution Function, and hill start assist Function are in Operation (During Pressure Decrease)
Component partsNot activatedWhen pressure decrease
Cut valve 1Power supply is not supplied (open)Power supply is not supplied (open)
Cut valve 2Power supply is not supplied (open)Power supply is not supplied (open)
Suction valve 1Power supply is not supplied (close)Power supply is not supplied (close)
Suction valve 2Power supply is not supplied (close)Power supply is not supplied (close)
ABS IN valvePower supply is not supplied (open)Power supply is not supplied (open)
ABS OUT valvePower supply is not supplied (close)Power supply is not supplied (close)
Each brake (fluid pressure)Pressure decreases
During pressure front RH brake decreased
  • Since the suction valve 1 and the ABS OUT valve close and the cut valve 1 and the ABS IN valve open, the fluid pressure applied on the front RH brake is reduced by supplying the fluid pressure to the master cylinder via the ABS IN valve and the cut valve 1. The pressurization for the right brake is controlled separately from the left brake.
During pressure front LH brake decreased
  • Since the suction valve 2 and the ABS OUT valve close and the cut valve 2 and the ABS IN valve open, the fluid pressure applied on the front LH brake is reduced by supplying the fluid pressure to the master cylinder via the ABS IN valve and the cut valve 2. The pressurization for the left brake is controlled separately from the right brake.
During pressure rear RH brake decreased
  • Since the suction valve 2 and the ABS OUT valve close and the cut valve 2 and the ABS IN valve open, the fluid pressure applied on the rear RH brake is reduced by supplying the fluid pressure to the master cylinder via the ABS IN valve and the cut valve 2. The pressurization for the right brake is controlled separately from the left brake.
During pressure rear LH brake decreased
  • Since the suction valve 1 and the ABS OUT valve close and the cut valve 1 and the ABS IN valve open, the fluid pressure applied on the rear LH brake is reduced by supplying the fluid pressure to the master cylinder via the ABS IN valve and the cut valve 1. The pressurization for the left brake is controlled separately from the right brake.
 
 
Component Parts and Function
Component partsFunction
Pump
  • Pressure the brake fluid and send.
  • Returns the brake fluid reserved in reservoir to master cylinder by reducing pressure.
MotorActivates the pump according to signals from ABS actuator and electric unit (control unit).
Cut valve 1
Cut valve 2
Shuts off the ordinary brake line from master cylinder.
Suction valve 1
Suction valve 2
Supplies the brake fluid from master cylinder to the pump.
ABS IN valveSwitches the fluid pressure line to increase or hold according.
ABS OUT valveSwitches the fluid pressure line to increase, hold or decrease according.
return check valveReturns the brake fluid from each brake to master cylinder by bypassing orifice of each valve when brake is released.
ReservoirTemporarily reserves the brake fluid drained from each brake, so that pressure efficiently decreases when decreasing pressure of each brake.
Pressure sensorDetects the brake fluid pressure and transmits signal to ABS actuator and electric unit (control unit).
 
 
VALVE OPERATION (ABS FUNCTION)
Each valve is operated and fluid pressure of brake is controlled.
 
 
When Brake Pedal is Applied
Component partsNot activatedWhen pressure increases
Cut valve 1Power supply is not supplied (open)Power supply is not supplied (open)
Cut valve 2Power supply is not supplied (open)Power supply is not supplied (open)
Suction valve 1Power supply is not supplied (close)Power supply is not supplied (close)
Suction valve 2Power supply is not supplied (close)Power supply is not supplied (close)
ABS IN valvePower supply is not supplied (open)Power supply is not supplied (open)
ABS OUT valvePower supply is not supplied (close)Power supply is not supplied (close)
Each brake (fluid pressure)Pressure increases
During pressure front RH brake increases
  • When the cut valve 1 and the ABS IN valve opens, brake fluid is supplied to the front RH brake from the master cylinder through the ABS IN valve. Brake fluid does not flow into the reservoir because the ABS OUT valve is closed.
During pressure front LH brake increases
  • When the cut valve 2 and the ABS IN valve opens, brake fluid is supplied to the front LH brake from the master cylinder through the ABS IN valve. Brake fluid does not flow into the reservoir because the ABS OUT valve is closed.
During pressure rear RH brake increases
  • When the cut valve 2 and the ABS IN valve opens, brake fluid is supplied to the rear RH brake from the master cylinder through the ABS IN valve. Brake fluid does not flow into the reservoir because the ABS OUT valve is closed.
During pressure rear LH brake increases
  • When the cut valve 1 and the ABS IN valve opens, brake fluid is supplied to the rear LH brake from the master cylinder through the ABS IN valve. Brake fluid does not flow into the reservoir because the ABS OUT valve is closed.
 
 
When ABS Function is in Operation (During Pressure Increases)
Component partsNot activatedWhen pressure increases
Cut valve 1Power supply is not supplied (open)Power supply is not supplied (open)
Cut valve 2Power supply is not supplied (open)Power supply is not supplied (open)
Suction valve 1Power supply is not supplied (close)Power supply is not supplied (close)
Suction valve 2Power supply is not supplied (close)Power supply is not supplied (close)
ABS IN valvePower supply is not supplied (open)Power supply is not supplied (open)
ABS OUT valvePower supply is not supplied (close)Power supply is not supplied (close)
Each brake (fluid pressure)Pressure increases
During pressure front RH brake increases
  • Brake fluid is supplied to the front RH brake from the master cylinder through the cut valve 1 and the ABS IN valve. Since the suction valve 1 and the ABS OUT valve is closed, the fluid does not flow into the reservoir. The amount of brake fluid supplied to the front RH brake from the master cylinder is controlled according to time that the ABS IN valve is not energized (time that the ABS IN valve is open).
During pressure front LH brake increases
  • Brake fluid is supplied to the front LH brake from the master cylinder through the cut valve 2 and the ABS IN valve. Since the suction valve 2 and the ABS OUT valve is closed, the fluid does not flow into the reservoir. The amount of brake fluid supplied to the front LH brake from the master cylinder is controlled according to time that the ABS IN valve is not energized (time that the ABS IN valve is open).
During pressure rear RH brake increases
  • Brake fluid is supplied to the rear RH brake from the master cylinder through the cut valve 2 and the ABS IN valve. Since the suction valve 2 and the ABS OUT valve is closed, the fluid does not flow into the reservoir. The amount of brake fluid supplied to the rear RH brake from the master cylinder is controlled according to time that the ABS IN valve is not energized (time that the ABS IN valve is open).
During pressure rear LH brake increases
  • Brake fluid is supplied to the rear LH brake from the master cylinder through the cut valve 1 and the ABS IN valve. Since the suction valve 1 and the ABS OUT valve is closed, the fluid does not flow into the reservoir. The amount of brake fluid supplied to the rear LH brake from the master cylinder is controlled according to time that the ABS IN valve is not energized (time that the ABS IN valve is open).
 
 
When ABS Function is Operating (During Pressure Holds)
Component partsNot activatedWhen pressure holds
Cut valve 1Power supply is not supplied (open)Power supply is not supplied (open)
Cut valve 2Power supply is not supplied (open)Power supply is not supplied (open)
Suction valve 1Power supply is not supplied (close)Power supply is not supplied (close)
Suction valve 2Power supply is not supplied (close)Power supply is not supplied (close)
ABS IN valvePower supply is not supplied (open)Power supply is supplied (close)
ABS OUT valvePower supply is not supplied (close)Power supply is not supplied (close)
Each brake (fluid pressure)Pressure holds
During pressure front RH brake holds
  • Since the ABS IN valve and the ABS OUT valve are closed, the front RH brake, master cylinder, and reservoir are blocked. This maintains fluid pressure applied on the front RH brake.
During pressure front LH brake holds
  • Since the ABS IN valve and the ABS OUT valve are closed, the front LH brake, master cylinder, and reservoir are blocked. This maintains fluid pressure applied on the front LH brake.
During pressure rear RH brake holds
  • Since the ABS IN valve and the ABS OUT valve are closed, the rear RH brake, master cylinder, and reservoir are blocked. This maintains fluid pressure applied on the rear RH brake.
During pressure rear LH brake holds
  • Since the ABS IN valve and the ABS OUT valve are closed, the rear LH brake, master cylinder, and reservoir are blocked. This maintains fluid pressure applied on the rear LH brake.
 
 
When ABS Function is in Operation (During Pressure Decreases)
Component partsNot activatedWhen pressure decreases
Cut valve 1Power supply is not supplied (open)Power supply is not supplied (open)
Cut valve 2Power supply is not supplied (open)Power supply is not supplied (open)
Suction valve 1Power supply is not supplied (close)Power supply is not supplied (close)
Suction valve 2Power supply is not supplied (close)Power supply is not supplied (close)
ABS IN valvePower supply is not supplied (open)Power supply is supplied (close)
ABS OUT valvePower supply is not supplied (close)Power supply is supplied (open)
Each brake (fluid pressure)Pressure decreases
During pressure front RH brake decreased
  • Since the ABS IN valve is closed and the ABS OUT valve is opened, fluid pressure applied on the front RH brake is supplied to the reservoir through the ABS OUT valve. This fluid pressure decreases when sent to the master cylinder by the pump.
During pressure front LH brake decreased
  • Since the ABS IN valve is closed and the ABS OUT valve is opened, fluid pressure applied on the front LH brake is supplied to the reservoir through the ABS OUT valve. This fluid pressure decreases when sent to the master cylinder by the pump.
During pressure rear RH brake decreased
  • Since the ABS IN valve is closed and the ABS OUT valve is opened, fluid pressure applied on the rear RH brake is supplied to the reservoir through the ABS OUT valve. This fluid pressure decreases when sent to the master cylinder by the pump.
During pressure rear LH brake decreased
  • Since the ABS IN valve is closed and the ABS OUT valve is opened, fluid pressure applied on the rear LH brake is supplied to the reservoir through the ABS OUT valve. This fluid pressure decreases when sent to the master cylinder by the pump.
 
 
When Brake Release
Component parsNot activatedWhen pressure decrease
Cut valve 1Power supply is not supplied (open)Power supply is not supplied (open)
Cut valve 2Power supply is not supplied (open)Power supply is not supplied (open)
Suction valve 1Power supply is not supplied (close)Power supply is not supplied (close)
Suction valve 2Power supply is not supplied (close)Power supply is not supplied (close)
ABS IN valvePower supply is not supplied (open)Power supply is not supplied (open)
ABS OUT valvePower supply is not supplied (close)Power supply is not supplied (close)
Each brake (fluid pressure)Pressure decreases
During pressure front RH brake release
  • Brake fluid is supplied to the front RH brake through the return check valve of the ABS IN valve and the cut valve 1, and returns to the master cylinder.
During pressure front LH brake release
  • Brake fluid is supplied to the front LH brake through the return check valve of the ABS IN valve and the cut valve 2, and returns to the master cylinder.
During pressure rear RH brake release
  • Brake fluid is supplied to the rear RH brake through the return check valve of the ABS IN valve and the cut valve 2, and returns to the master cylinder.
During pressure rear LH brake release
  • Brake fluid is supplied to the rear LH brake through the return check valve of the ABS IN valve and the cut valve 1, and returns to the master cylinder.
 
 
Component Parts and Function
Component partsFunction
Pump
  • Pressure the brake fluid and send.
  • Returns the brake fluid reserved in reservoir to master cylinder by reducing pressure.
MotorActivates the pump according to signals from ABS actuator and electric unit (control unit).
Cut valve 1
Cut valve 2
Shuts off the ordinary brake line from master cylinder.
Suction valve 1
Suction valve 2
Supplies the brake fluid from master cylinder to the pump.
ABS IN valveSwitches the fluid pressure line to increase or hold according.
ABS OUT valveSwitches the fluid pressure line to increase, hold or decrease according.
return check valveReturns the brake fluid from each brake to master cylinder by bypassing orifice of each valve when brake is released.
ReservoirTemporarily reserves the brake fluid drained from each brake, so that pressure efficiently decreases when decreasing pressure of each brake.
Pressure sensorDetects the brake fluid pressure and transmits signal to ABS actuator and electric unit (control unit).
 
 
CONDITION FOR TURN ON THE WARNING LIGHT
Turns ON when electric motor switch ON and turns OFF when the system is normal, for bulb check purposes.
noteAbout electric parking brake warning light: Refer to System Description.
Condition (status)ABS warning lightBrake warning lightASC warning light
Electric motor switch OFF (Auto ACC function OFF)OFFOFFOFF
For approx. 1 second after the electric motor switch is ONONONON
Approx. 1 second after electric motor switch is ON (when the before engine starts, system is in normal operation)OFFONOFF
After engine startsOFFOFFOFF
When brake fluid is less than the specified level (brake fluid level switch ON)OFFONON
ASC function is malfunctioningOFFOFFON
TCS function is malfunctioningOFFOFFON
ABS function is malfunctioningONOFFON
EBD function is malfunctioningONONON
Brake limited slip differential (BLSD) function is malfunctioningOFFOFFON
Brake assist function is malfunctioningOFFOFFON
Brake force distribution function is malfunctioningOFFOFFON
hill start assist function is malfunctioningOFFOFFON
Brake vacuum sensor function is malfunctioningOFFONOFF
ASC function is operatingOFFOFFBlinking
TCS function is operatingOFFOFFBlinking
ABS function is operatingOFFOFFOFF
EBD function is operatingOFFOFFOFF
Brake limited slip differential (BLSD) function is operatingOFFOFFBlinking
Brake assist function is operatingOFFOFFOFF
Brake force distribution function is operatingOFFOFFOFF
hill start assist function is operatingOFFOFFOFF
 
 
CONDITION FOR TURN ON THE INDICATOR LIGHT
Turns ON when electric motor switch turns ON and OFF when the system is normal, for bulb check purposes.
noteAbout electric parking brake indicator light: Refer to System Description.
Condition (status)ASC OFF indicator light
Electric motor switch OFF (Auto ACC function OFF)OFF
For approx. 1 second after the electric motor switch is ONON
Approx. 1 second after electric motor switch is ON (when system is in normal operation)OFF
After engine starts (when system is in normal operation)OFF
ASC setting is OFF (ASC OFF indicator is turn ON)ON
ASC function is malfunctioningOFF
TCS function is malfunctioningOFF