BRC-18
< SYSTEM DESCRIPTION >[VDC/TCS/ABS]
SYSTEM
ABS Function Starts Operating (Pressure Holds)
Front RH brake caliper
• Since the ABS IN valve and the ABS OUT valve are cl
osed, the front RH brake caliper, master cylinder, and
reservoir are blocked. This maintains fluid pressure applied on the front RH brake caliper.
Front LH brake caliper
• Since the ABS IN valve and the ABS OUT valve are cl osed, the front LH brake caliper, master cylinder, and
reservoir are blocked. This maintains fluid pressure applied on the front LH brake caliper.
Rear RH brake caliper
• Since the ABS IN valve and the ABS OUT valve are cl osed, the rear RH brake caliper, master cylinder, and
reservoir are blocked. This maintains fluid pressure applied on the rear RH brake caliper.
Rear LH brake caliper
• Since the ABS IN valve and the ABS OUT valve are cl osed, the rear LH brake caliper, master cylinder, and
reservoir are blocked. This maintains fluid pressure applied on the rear LH brake caliper.
ALFIA0313GB
Name Not activated During pressure holds
Cut valve 1 Power supply is not supplied (open) Power supply is not supplied (open)
Cut valve 2 Power supply is not supplied (open) Power supply is not supplied (open)
Suction valve 1 Power supply is not supplied (close) Power supply is not supplied (close)
Suction valve 2 Power supply is not supplied (close) Power supply is not supplied (close)
ABS IN valve Power supply is not supplied (open) Power supply is supplied (close)
ABS OUT valve Power supply is not supplied (close) Power supply is not supplied (close)
Each brake caliper (fluid pressure) — Pressure holds
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM
SYSTEMBRC-19
< SYSTEM DESCRIPTION > [VDC/TCS/ABS]
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ABS Function Operating
(Pressure Decreases)
Front RH brake caliper
• Since the ABS IN valve is closed and the ABS OUT valve is opened, fluid pressure applied on the front RH
brake caliper is supplied to the reservoir through the ABS OUT valve. This fluid pressure decreases when
sent to the master cylinder by the pump.
Front LH brake caliper• Since the ABS IN valve is closed and the ABS OUT valve is opened, fluid pressure applied on the front LH
brake caliper is supplied to the reservoir through the ABS OUT valve. This fluid pressure decreases when
sent to the master cylinder by the pump.
Rear RH brake caliper• Since the ABS IN valve is closed and the ABS OUT valve is opened, fluid pressure applied on the rear RH
brake caliper is supplied to the reservoir through the ABS OUT valve. This fluid pressure decreases when
sent to the master cylinder by the pump.
Rear LH brake caliper
• Since the ABS IN valve is closed and the ABS OUT valve is opened, fluid pressure applied on the rear LH
brake caliper is supplied to the reservoir through the ABS OUT valve. This fluid pressure decreases when
sent to the master cylinder by the pump.
ALFIA0314GB
Name Not activated During pressure decreases
Cut valve 1 Power supply is not supplied (open) Power supply is not supplied (open)
Cut valve 2 Power supply is not supplied (open) Power supply is not supplied (open)
Suction valve 1 Power supply is not supplied (close) Power supply is not supplied (close)
Suction valve 2 Power supply is not supplied (close) Power supply is not supplied (close)
ABS IN valve Power supp ly is not supplied (open) Power supply is supplied (close)
ABS OUT valve Power supp ly is not supplied (close) Power supp ly is supplied (open)
Each brake caliper (fluid pressure) — Pressure decreases
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM
BRC-20
< SYSTEM DESCRIPTION >[VDC/TCS/ABS]
SYSTEM
ABS Function Operating
(Pressure Increases)
Front RH brake caliper
• Brake fluid is supplied to the front RH brake caliper from the master cylinder through the cut valve 1 and the
ABS IN valve. Since the suction valve 1 and the ABS OU T valve is closed, the fluid does not flow into the
reservoir. The amount of brake fluid supplied to the fr ont RH brake caliper from the master cylinder is con-
trolled according to time that the ABS IN valve is not energized (time that the ABS IN valve is open).
Front LH brake caliper• Brake fluid is supplied to the front LH brake caliper from the master cylinder through the cut valve 2 and the
ABS IN valve. Since the suction valve 2 and the ABS OU T valve is closed, the fluid does not flow into the
reservoir. The amount of brake fluid supplied to the fr ont LH brake caliper from the master cylinder is con-
trolled according to time that the ABS IN valve is not energized (time that the ABS IN valve is open).
Rear RH brake caliper• Brake fluid is supplied to the rear RH brake caliper from the master cylinder through the cut valve 2 and the
ABS IN valve. Since the suction valve 2 and the ABS OU T valve is closed, the fluid does not flow into the
reservoir. The amount of brake fluid supplied to the r ear RH brake caliper from the master cylinder is con-
trolled according to time that the ABS IN valve is not energized (time that the ABS IN valve is open).
Rear LH brake caliper
• Brake fluid is supplied to the rear LH brake caliper from the master cylinder through the cut valve 1 and the
ABS IN valve. Since the suction valve 1 and the ABS OU T valve is closed, the fluid does not flow into the
ALFIA0312GB
Name Not activated During pressure increases
Cut valve 1 Power supply is not supplied (open) Power supply is not supplied (open)
Cut valve 2 Power supply is not supplied (open) Power supply is not supplied (open)
Suction valve 1 Power supply is not supplied (close) Power supply is not supplied (close)
Suction valve 2 Power supply is not supplied (close) Power supply is not supplied (close)
ABS IN valve Power supply is not supplied (open) Power supply is not supplied (open)
ABS OUT valve Power supply is not supplied (close) Power supply is not supplied (close)
Each brake caliper (fluid pressure) — Pressure increases
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM
SYSTEMBRC-21
< SYSTEM DESCRIPTION > [VDC/TCS/ABS]
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reservoir. The amount of brake fluid supplied to the r ear LH brake caliper from the master cylinder is con-
trolled according to time that the ABS IN valve is not energized (time that the ABS IN valve is open).
Brake Release
Front RH brake caliper• Brake fluid is supplied to the front RH brake caliper through the return check valve of the ABS IN valve and
the cut valve 1, and returns to the master cylinder.
Front LH brake caliper• Brake fluid is supplied to the front LH brake caliper through the return check valve of the ABS IN valve and
the cut valve 2, and returns to the master cylinder.
Rear RH brake caliper• Brake fluid is supplied to the rear RH brake caliper through the return check valve of the ABS IN valve and the cut valve 2, and returns to the master cylinder.
Rear LH brake caliper• Brake fluid is supplied to the rear LH brake caliper 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
ALFIA0315GB
Name Not activated During brake release
Cut valve 1 Power supply is not supplied (open) Power supply is not supplied (open)
Cut valve 2 Power supply is not supplied (open) Power supply is not supplied (open)
Suction valve 1 Power supply is not supplied (close) Power supply is not supplied (close)
Suction valve 2 Power supply is not supplied (close) Power supply is not supplied (close)
ABS IN valve Power supp ly is not supplied (open) Power supp ly is not supplied (open)
ABS OUT valve Power supp ly is not supplied (close) Power supply is not supplied (close)
Each brake caliper (fluid pressure) — Pressure decreases
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM
BRC-22
< SYSTEM DESCRIPTION >[VDC/TCS/ABS]
SYSTEM
CONDITIONS FOR INDICATOR LAMP ILLUMINATION
• Turns ON when VDC and TCS functions are switched to
non-operational status (OFF) by VDC OFF switch.
• Turns ON when ignition switch turns ON and turns OF F when the system is normal, for bulb check purposes.
CONDITIONS FOR WARNING LAMP ILLUMINATION
Turns ON when ignition switch turns ON and turns OFF when the system is normal, for bulb check purposes.
Component Function
Pump Returns the brake fluid reserved in reservoir to master cylinder by reducing pressure.
Motor Activates the pu mp according to signals from ABS actuator and el ectric 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 valve Switches the fluid pressure line to increase or hold according to signals from control unit.
ABS OUT valve Switches the fluid pressure li ne to increase, hold or decrease according to si gnals from control unit.
Return check valve Returns the brake fluid from brake caliper to master cylinder by bypassing orifice of each valve when
brake is released.
Reservoir Temporarily reserves the brake fluid drained from brake caliper, so that pressure efficiently decreas-
es when decreasing pressure of brake caliper.
Pressure sensor Detects the brak e fluid pressure and transmits signal to ABS actuator and electric unit (control unit).
Condition (status) VDC OFF indicator lamp SLIP indicator lamp
Ignition switch OFF OFF OFF
For approx. 1 second after the ignition switch
is turned ON ON ON
Approx. 1 second after ignition switch is
turned ON (when the system is in normal op-
eration) OFF OFF
When VDC OFF switch is ON (VDC function
and TCS function are OFF) ON OFF
VDC function is malfunctioning OFF ON
TCS function is malfunctioning OFF ON
Condition (status) ABS warning lamp Brake warning lamp
Ignition switch OFF OFF OFF
For approx. 1 second after the ignition switch
is turned ON ON ON
Approx. 1 second after ignition switch is
turned ON (when the system is in normal op-
eration) OFF OFF
After engine starts OFF OFF
When parking brake operates (parking brake
switch ON) OFF ON
When brake fluid is less than the specified
level (brake fluid level switch ON) OFF ON
When vacuum sensor is malfunctioning OFF ON
VDC function is malfunctioning OFF OFF
TCS function is malfunctioning OFF OFF
ABS function is malfunctioning ON OFF
EBD function is malfunctioning ON ON
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM
BRC-24
< SYSTEM DESCRIPTION >[VDC/TCS/ABS]
SYSTEM
• Brake force control function
at braking hard detects driver′s brake operations with the pressure sensor,
judges a brake booster ′s maximum brake power function by using information from the vacuum sensor, and
enhances more powerful braking force by controlling brakes of four wheels.
• VDC warning lamp blinks while VDC function is in operati on and indicates to the driver that the function is in
operation.
• CONSULT can be used to diagnose the system.
• Fail-safe function is adopted. When a malfunction occurs in VDC function, the control is suspended for VDC
function and TCS function. However, ABS functi on and EBD function operate normally. Refer to BRC-41,
"Fail-safe".
INPUT SIGNAL AND OUTPUT SIGNAL
Major signal transmission between each unit via communication lines is shown in the following table.
OPERATION CHARACTERISTICS
VDC Function That Prevents Oversteer Tendency
• During cornering, brake force (brake fluid pressu re) is applied on front wheel and rear wheel on the outer
side of turn. Momentum is generated directing the vehicle toward the outer side of the turn. Oversteer is pre-
vented.
• Changing driving lane on a slippery road, when there may be a tendency to oversteer, engine output is con- trolled as well as brake force (brake fluid pr essure) of 4 wheels. Oversteer tendency decreases.
Component Signal description
ECM Transmits the following signals to ABS actuator and electric unit (control unit) via CAN commu-
nication.
• Acceleration pedal position signal
• Engine speed signal
• Target throttle position signal
TCM Transmits the current gear positi
on signal to ABS actuator and el ectric unit (control unit) via
CAN communication.
Steering angle sensor Transmits the steering angle sensor signal to ABS actuator and electric unit (control unit) via
CAN communication.
Combination meter Transmits the following signals to ABS actuator and electric unit (control unit) via CAN commu-
nication.
• Brake fluid level switch signal
• parking brake switch signal
Receives the following signals from ABS actuator and electric unit (control unit) via CAN com-
munication.
• VDC OFF indicator lamp signal
• SLIP indicator lamp signal
ALFIA0339GB
ALFIA0340GB
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM
SYSTEMBRC-25
< SYSTEM DESCRIPTION > [VDC/TCS/ABS]
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VDC Function That Prevents Understeer Tendency
• During cornering, brake force (brake fluid pressure) is applied on front wheel and rear wheel on the inner
side of turn. Momentum is generated di recting the vehicle toward the inner side of the turn. Understeer is
prevented.
• Applying brakes during cornering on a slippery road, when there may be a tendency to understeer, engine output is controlled as well as brake force (bra ke fluid pressure) of 4 wheels. Understeer tendency
decreases.
VDC/TCS/ABS : TCS FunctionINFOID:0000000009463754
SYSTEM DIAGRAM
SYSTEM DESCRIPTION
JPFIC0137GB
ALFIA0341GB
ALFIA0298GB
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM
BRC-26
< SYSTEM DESCRIPTION >[VDC/TCS/ABS]
SYSTEM
• Wheel spin status of drive wheel is detected by wheel sensor of 4
wheels. Engine output and transmission shift status is controlled
so that slip rate of drive wheels is in appropriate level. When wheel
spin occurs on drive wheel, ABS actuator and electric unit (control
unit) perform brake force control of LH and RH drive wheels (apply
brake force by increasing brake fluid pressure of drive wheel) and
decrease engine torque by engine torque control. Wheel spin
amount decreases. Engine torque is controlled to appropriate
level.
• TCS function can be switched to non-operational status (OFF) by operating VDC OFF switch. In this case, VDC OFF indicator lamp
turns ON.
• SLIP indicator lamp blinks while TCS function is in operation and
indicates to the driver that the function is in operation.
• CONSULT can be used to diagnose the system.
• Fail-safe function is adopted. When a malfunction occurs in TCS
function, the control is sus pended for VDC function and TCS func-
tion. However, ABS function and EBD function operate normally.
Refer to BRC-41, "Fail-safe"
.
INPUT SIGNAL AND OUTPUT SIGNAL
Major signal transmission between each unit via communication lines is shown in the following table.
JPFIC0139GB
Component Signal description
ECM Transmits the following signals to ABS actuator and electric unit (control unit) via CAN commu-
nication.
• Accelerator pedal position signal
• Engine speed signal
• Target throttle position signal
TCM Transmits the current gear positi
on signal to ABS actuator and el ectric unit (control unit) via
CAN communication.
Steering angle sensor Transmits the steering angle sensor signal to ABS actuator and electric unit (control unit) via
CAN communication.
Combination meter Transmits the following signals to ABS actuator and electric unit (control unit) via CAN commu-
nication.
• Brake fluid level switch signal
• Parking brake switch signal
Receives the following signals from ABS actuator and electric unit (control unit) via CAN com-
munication.
• VDC OFF indicator lamp signal
• SLIP indicator lamp signal
Revision: November 20132014 Altima NAMRevision: November 20132014 Altima NAM