BRC-1
BRAKE CONTROL SYSTEM
F BRAKES
CONTENTS
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SECTION BRC
A
B
BRC
Revision: 2004 November 2004 FX35/FX45
BRAKE CONTROL SYSTEM
VDC/TCS/ABS
PRECAUTIONS .......................................................... 3
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” .................................................................. 3
Precautions for Brake System .................................. 3
Precautions for Brake Control .................................. 3
PREPARATION ........................................................... 5
Special Service Tools ............................................... 5
Commercial Service Tools ........................................ 5
ON-VEHICLE SERVICE ............................................. 6
Adjustment of Steering Angle Sensor Neutral Posi-
tion ........................................................................... 6
Calibration of Decel G-sensor (AWD Model) ............ 6
SYSTEM DESCRIPTION ............................................ 8
System Diagram ....................................................... 8
VDC Function ........................................................... 8
TCS Function ........................................................... 8
ABS Function ........................................................... 8
EBD Function ........................................................... 9
Fail-Safe Function .................................................... 9
VDC / TCS SYSTEM ............................................. 9
ABS, EBD SYSTEM .............................................. 9
Hydraulic Circuit Diagram ...................................... 10
CAN COMMUNICATION ...........................................11
System Description ................................................. 11
TROUBLE DIAGNOSIS ............................................ 12
How to Proceed With Diagnosis ............................. 12
BASIC CONCEPT ............................................... 12
DIAGNOSIS FLOWCHART ................................ 13
ASKING COMPLAINTS ...................................... 14
EXAMPLE OF DIAGNOSIS SHEET ................... 14
Component Installation Location ............................ 15
Schematic .............................................................. 16
Wiring Diagram — VDC — ..................................... 17
Control Unit Input/Output Signal Standard ............. 23
REFERENCE VALUE FROM CONSULT-II ......... 23
CONSULT-II Functions ........................................... 25
CONSULT-II MAIN FUNCTION ........................... 25
CONSULT-II BASIC OPERATION PROCEDURE ... 26
SELF-DIAGNOSIS .............................................. 27
DATA MONITOR ................................................. 30
ACTIVE TEST ..................................................... 33
For Fast and Accurate Diagnosis ........................... 35
PRECAUTIONS FOR DIAGNOSIS ..................... 35
Basic Inspection ..................................................... 36
BASIC INSPECTION 1: BRAKE FLUID
AMOUNT, LEAKS, AND BRAKE PADS INSPEC-
TION .................................................................... 36
BASIC INSPECTION 2: POWER SYSTEM TER-
MINAL LOOSENESS AND BATTERY INSPEC-
TION .................................................................... 36
BASIC INSPECTION 3: ABS WARNING LAMP,
VDC OFF INDICATOR LAMP, SLIP INDICATOR
LAMP AND BRAKE WARNING LAMP INSPEC-
TION .................................................................... 37
Inspection 1: Wheel Sensor System ....................... 37
Inspection 2: Engine System .................................. 39
Inspection 3: VDC/TCS/ABS Control Unit System ... 40
Inspection 4: Pressure Sensor System .................. 40
Inspection 5: Steering Angle Sensor System ......... 42
Inspection 6: Yaw Rate/Side G-Sensor (2WD
model), Yaw Rate/Side/Decel G-sensor (AWD mod-
els) System ............................................................. 44
Inspection 7: Solenoid and VDC Change-Over
Valve System .......................................................... 46
Inspection 8: Actuator Motor System ...................... 47
Inspection 9: ABS Actuator and Electric Unit (Con-
trol Unit) Power Supply and Ground System .......... 48
Inspection 10: Stop Lamp Switch System .............. 50
Inspection 11: Brake Fluid Level Switch System .... 51
Inspection 12: When “ST ANG SEN SIGNAL”
Appears on Self-Diagnosis Results Display ........... 52
Inspection 13: When “DECEL G SEN SET” Appears
on Self-Diagnosis Results Display (AWD Model) ... 52
Inspection 14: CAN Communication System .......... 53
Component Inspection ............................................ 53
VDC OFF SWITCH ............................................. 53
Symptom 1: Excessive ABS Function Operation
BRC-2Revision: 2004 November 2004 FX35/FX45Frequency ............................................................... 53
Symptom 2: Unexpected Pedal Reaction ............... 54
Symptom 3: The Braking Distance Is Long ............ 54
Symptom 4: The ABS Function Does Not Operate ... 54
Symptom 5: Pedal Vibration or ABS Operation
Sound Occurs ......................................................... 55
Symptom 6: Vehicle Jerks During VDC/TCS/ABS
Control .................................................................... 55
WHEEL SENSORS ................................................... 57
Removal and Installation ........................................ 57
REMOVAL ........................................................... 57
INSTALLATION .................................................... 57
SENSOR ROTOR ...................................................... 59
Removal and Installation ........................................ 59
REMOVAL ........................................................... 59
INSTALLATION .................................................... 59ACTUATOR AND ELECTRIC UNIT (ASSEMBLY) ... 60
Removal and Installation ......................................... 60
REMOVAL ............................................................ 60
INSTALLATION .................................................... 60
G SENSOR ................................................................ 62
Removal and Installation ......................................... 62
REMOVAL ............................................................ 62
INSTALLATION .................................................... 62
STEERING ANGLE SENSOR ................................... 63
Removal and Installation ......................................... 63
REMOVAL ............................................................ 63
INSTALLATION .................................................... 63
BRC-4
[VDC/TCS/ABS]
PRECAUTIONS
Revision: 2004 November 2004 FX35/FX45
If aftermarket parts (car stereo, CD player, etc.) have been installed, check for incidents such as harness
pinches, open circuits, and improper wiring.
If the following components are replaced with non-genuine components or converted, VDC OFF indicator
lamp and SLIP indicator lamp may turn on or the VDC system may not operate properly. Components
related to suspension (Shock Absorber, Strut, Spring, Bush, etc.), Tires, wheels (exclude specified size),
components related to brake (Pad, Rotor, Caliper, etc.), components related to engine (Muffler, ECM,
etc.), components related to body reinforcement (Roll bar, Tower bar, etc.).
Driving in the condition of breakage or excessive wear of suspension, tires or components related to the
brakes may cause VDC OFF indicator lamp and SLIP indicator lamp turn on, and the VDC system may
not operate properly.
When the TCS or VDC is activated by sudden acceleration or sudden turn, some noise may occur. The
noise is a result of the normal operation of the TCS and VDC.
When driving on roads which have extreme slopes (such as mountainous roads) or high banks (such as
sharp carves on a freeway), the VDC may not operate normally, or VDC OFF indicator lamp and SLIP
indicator lamp may turn on. However, this is not a malfunction, if normal operation can be resumed after
restarting engine.
Sudden turns (such as spin turns, acceleration turns), drifting, etc. When VDC function is OFF (VDC SW
ON) may cause the G -sensor system indicate a malfunction. However, this is not a malfunction, if normal
operation can be resumed after restarting engine.
BRC-6
[VDC/TCS/ABS]
ON-VEHICLE SERVICE
Revision: 2004 November 2004 FX35/FX45
ON-VEHICLE SERVICEPFP:00000
Adjustment of Steering Angle Sensor Neutral PositionAFS001S9
In case of doing work that applies to the list below, make sure to adjust neutral position of steering angle sen-
sor before running vehicle.
×: Required
–: Not required
CAUTION:
To adjust neutral position of steering angle sensor, make sure to use CONSULT-II.
(Adjustment cannot be done without CONSULT-II.)
1. Stop vehicle with front wheels in straight-ahead position.
2. Connect CONSULT-II and CONSULT-II CONVERTER to data link connector on vehicle, and turn ignition
switch ON (do not start engine).
CAUTION:
If CONSULT-II is used with no connection of CONSULT-II CONVERTER, malfunctions might be
detected in self-diagnosis depending on control unit which carry out CAN communication.
3. Touch “ABS”, “WORK SUPPORT” and “ST ANGLE SENSOR ADJUSTMENT” on CONSULT-II screen in
this order. Refer to BRC-26, "
CONSULT-II BASIC OPERATION PROCEDURE" .
4. Touch “START”.
CAUTION:
Do not touch steering wheel while adjusting steering angle
sensor.
5. After approximately 10 seconds, touch “END”. (After approxi-
mately 60 seconds, it ends automatically.)
6. Turn ignition switch OFF, then turn it ON again.
CAUTION:
Be sure to carry out above operation.
7. Run vehicle with front wheels in straight-ahead position, then
stop.
8. Select “DATA MONITOR”, “SELECTION FROM MENU”, and “STR ANGLE SIG” on CONSULT-II screen.
Then make sure “STR ANGLE SIG” is within 0 ±3.5 deg. If value is more than specification, repeat steps 3
to 7.
9. Erase memory of ABS actuator and electric unit (control unit) and ECM.
10. Turn ignition switch OFF.
Calibration of Decel G-sensor (AWD Model)AFS001TQ
NOTE:
After removing/installing or replacing yaw rate/side/decel G-sensor, ABS actuator and electric unit (control
unit), suspension components, or after adjusting wheel alignment make sure to calibrate of decel G-sensor
before running vehicle.
CAUTION:
To calibrate decel G-sensor, make sure to use CONSULT-II. (Adjustment cannot be done without CON-
SULT-II.)
Situation Adjustment of Steering Angle Sensor Neutral Position
Removing/Installing ABS actuator and electric unit (control unit)−
Replacing ABS actuator and electric unit (control unit)×
Removing/Installing steering angle sensor×
Removing/Installing steering components×
Removing/Installing suspension components×
Change 4 tires to new ones –
Tire rotation–
Adjusting wheel alignment×
SFIA0371E
ON-VEHICLE SERVICE
BRC-7
[VDC/TCS/ABS]
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BRC
Revision: 2004 November 2004 FX35/FX45
1. Stop vehicle with front wheels in straight-ahead position.
CAUTION:
The work should be done at a horizontal place when vehicle is in the unloaded vehicle condi-
tion.
Keep all tires inflated to correct pressures. Adjust the tire pressure to the specified pressure
value.
2. Connect CONSULT-II and CONSULT-II CONVERTER to data link connector on vehicle, and turn ignition
switch ON (do not start engine).
CAUTION:
If CONSULT-II is used with no connection of CONSULT-II CONVERTER, malfunctions might be
detected in self-diagnosis depending on control unit which carry out CAN communication.
3. Touch “ABS”, “WORK SUPPORT” and “DECEL G-SEN CALIBRATION” on CONSULT-II screen in this
order. Refer to BRC-26, "
CONSULT-II BASIC OPERATION PROCEDURE" .
4. Touch “START”.
CAUTION:
Set vehicle as shown in the display.
5. After approximately 10 seconds, touch “END”. (After approxi-
mately 60 seconds, it ends automatically.)
6. Turn ignition switch OFF, then turn it ON again.
CAUTION:
Be sure to carry out above operation.
7. Run vehicle with front wheels in straight-ahead position, then
stop.
8. Select “DATA MONITOR”, “SELECTION FROM MENU”, and
“DECEL G-SEN” on CONSULT-II screen. Then make sure “DECEL G-SEN” is within 0 ±0.08 G. If value is
more than specification, repeat steps 3 to 7.
9. Erase memory of ABS actuator and electric unit (control unit) and ECM.
10. Turn ignition switch OFF.
SFIA1162E
BRC-8
[VDC/TCS/ABS]
SYSTEM DESCRIPTION
Revision: 2004 November 2004 FX35/FX45
SYSTEM DESCRIPTIONPFP:00000
System DiagramAFS001SB
VDC FunctionAFS001SC
In addition to the TCS/ABS function, the driver steering amount and brake operation amount are detected
from steering angle sensor and pressure sensor, and the vehicle's driving status (amount of under steer-
ing / over steering) is determined from information from G-sensor, wheel sensor, etc., and this information
is used to improve vehicle stability by controlling the braking and engine power to all four wheels.
SLIP indicator lamp flashes to inform the driver of VDC operation.
During VDC operation, body and brake pedal lightly vibrate and mechanical noises may be heard. This is
normal.
ABS warning lamp, VDC OFF indicator lamp, and SLIP indicator lamp might turn on when vehicle is sub-
ject to strong shaking or large vibration, such as when vehicle is on a turn table, a ship or a steep slope
such as bank while engine is running. In this case, restart engine on a normal road, and if ABS warning
lamp, VDC OFF indicator lamp, and SLIP indicator lamp turn off, there is no problem.
TCS FunctionAFS001SD
The wheel spin of the drive wheels is detected by ABS actuator and electric unit (control unit) from the
wheel speed signals from four wheels, so if wheel spin occurs, drive wheel right and left brake fluid pres-
sure control and engine fuel cut are performed while throttle value is restricted to reduce the engine
torque and decrease the amount of wheel spin. In addition, the degree throttle is opened is controlled to
achieve the optimum engine torque.
Depending on road circumstances, the driver may have a sluggish feel. This is normal, because the opti-
mum traction has the highest priority under TCS operation.
TCS may be activated any time vehicle suddenly accelerates, suddenly down/upshifts, or is driven on a
road with a varying surface friction coefficient.
During TCS operation, it informs a driver of system operation by flashing SLIP indicator lamp.
ABS FunctionAFS001SE
The anti-lock brake system is a function that detects wheel revolution while braking, and it improves han-
dling stability during sudden braking by electrically preventing 4 wheel lock. Maneuverability is also
improved for avoiding obstacles.
If the electrical system breaks down, then the fail-safe function starts, the ABS becomes inoperative, and
ABS warning lamp turns on.
Electrical system diagnosis by CONSULT-II is available.
During ABS operation, brake pedal lightly vibrates and a mechanical noise may be heard. This is normal.
SFIA1160E
SYSTEM DESCRIPTION
BRC-9
[VDC/TCS/ABS]
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BRC
Revision: 2004 November 2004 FX35/FX45
When starting engine, or just after starting vehicle, brake pedal may vibrate or motor operating noises
may be heard from engine compartment. This is a normal status of operation check.
Stopping distance may be longer than that of vehicles without ABS when vehicle drives on rough, gravel,
or snow-covered (fresh, deep snow) roads.
EBD FunctionAFS001SF
Electronic brake distributor is a function that detects subtle slippages between front and rear wheels dur-
ing braking, and it improves handling stability by electronically controlling the brake fluid pressure which
results in reduced rear wheel slippage.
In case of electrical system break down, the fail-safe function is activated, EBD and ABS becomes inoper-
ative, and ABS warning lamp and brake warning lamp are turned on.
Electrical system diagnosis by CONSULT-II is available.
During EBD operation, brake pedal lightly vibrates and a mechanical noise may be heard. This is normal.
When starting engine, or just after starting vehicle, brake pedal may vibrate or motor operating noises
may be heard from engine compartment. This is a normal status of operation check.
Stopping distance may be longer than that of vehicles without EBD when vehicle drives on rough, gravel,
or snow-covered (fresh, deep snow) roads.
Fail-Safe FunctionAFS001SG
VDC / TCS SYSTEM
In case of malfunction in the VDC/TCS system, VDC OFF indicator lamp and SLIP indicator lamp are turned
on, and the condition of vehicle is the same as the condition of vehicles without VDC/TCS system. In case of
malfunction in the VDC/TCS system, the ABS control continues to operate normally without VDC/TCS control.
CAUTION:
If the fail-safe function is activated, then perform the self-diagnosis for VDC/TCS/ABS control system.
ABS, EBD SYSTEM
In case of electrical malfunctions with the ABS, ABS warning lamp, VDC OFF indicator lamp and SLIP indica-
tor lamp will turn on. In case of electrical malfunctions with the EBD, brake warning lamp, ABS warning lamp,
VDC OFF indicator lamp and SLIP indicator lamp will turn on. Simultaneously, the VDC/TCS/ABS become one
of the following conditions of the fail-safe function.
1. For malfunction of ABS, only the EBD is activated and the condition of vehicle is the same condition of
vehicles without TCS/ABS system.
2. For malfunction of EBD, EBD and ABS become inoperative, and the condition of vehicle is the same as
the condition of vehicles without TCS/ABS, EBD system.
NOTE:
In condition 1 described above, an ABS self-diagnosis sound may be heard. That is a normal condition
because a self-diagnosis for “Key Switch ON” and “the First Starting” are being performed.
TROUBLE DIAGNOSIS
BRC-23
[VDC/TCS/ABS]
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BRC
Revision: 2004 November 2004 FX35/FX45
Control Unit Input/Output Signal StandardAFS001SP
REFERENCE VALUE FROM CONSULT-II
CAUTION:
The display shows ABS actuator and electric unit (control unit) calculation data, so a normal value
might be displayed even in the event the output circuit (harness) is open or short-circuited.
Monitor item Display contentData monitor
Note: Error inspection
checklist
ConditionReference value in
normal operation
SLCT LVR POSI A/T shift positionP: P position
R: R position
N: N position
D: D position
—
GEAR A/T gear position1: 1st gear
2: 2nd gear
3: 3rd gear
4: 4th gear
5: 5th gear
FR RH SENSOR
FR LH SENSOR
RR RH SENSOR
RR LH SENSORWheel speedVehicle stopped 0 [km/h (MPH)]
BRC-37, "
Inspection 1:
Wheel Sensor System"Vehicle running (Note 1)Almost in accor-
dance with speed-
ometer display
(within ±10 %)
ACCEL POS SIG Open/close condition
of throttle valve (linked
with accelerator pedal).Accelerator pedal not
depressed (ignition switch is
ON)0 %
Communication circuit
between VDC/TCS/ABS
control unit and ECM
Depress accelerator pedal
(ignition switch is ON)0 to 100 %
ENGINE SPEED With engine runningWith engine stopped 0 rpm
EC section
Engine runningAlmost in accor-
dance with
tachometer display
STR ANGLE SIGSteering angle
detected by steering
angle sensorStraight-ahead Approx. 0 degBRC-42, "
Inspection 5:
Steering Angle Sensor
System"Steering wheel turned –756 to 756 deg
YAW RATE SENYaw rate detected by
yaw rate sensorVehicle stopped Approx. 0 d/sBRC-44, "
Inspection 6:
Yaw Rate/Side G-Sen-
sor (2WD model), Yaw
Rate/Side/Decel G-sen-
sor (AWD models) Sys-
tem"
Vehicle running –100 to 100 d/s
SIDE G-SENSORTransverse G detected
by side G-sensorVehicle stopped
Approx. 0 m/s
2BRC-44, "Inspection 6:
Yaw Rate/Side G-Sen-
sor (2WD model), Yaw
Rate/Side/Decel G-sen-
sor (AWD models) Sys-
tem"
Vehicle running
–16.7 to 16.7 m/s2
PRESS SENSORBrake fluid pressure
detected by pressure
sensorWith ignition switch turned ON
and brake pedal releasedApprox. 0 bar
BRC-40, "
Inspection 4:
Pressure Sensor Sys-
tem"With ignition switch turned ON
and brake pedal depressed0 to 170 bar
BATTERY VOLTBattery voltage sup-
plied to ABS actuator
and electric unit (con-
trol unit)Ignition switch ON 10 to 16 VBRC-48, "
Inspection 9:
ABS Actuator and Elec-
tric Unit (Control Unit)
Power Supply and
Ground System"
STOP LAMP SW Brake pedal operationBrake pedal depressed ONBRC-50, "
Inspection 10:
Stop Lamp Switch Sys-
tem"Brake pedal not depressed OFF