brakes TOYOTA RAV4 2006 Service Repair Manual

CHASSIS - 4WD SYSTEM CH-66
4WD SYSTEM
DESCRIPTION
The 4WD system of the ’06 RAV4 uses an active torque control 4WD system.
It is a compact, lightweight, and high performance 4WD system that optimally controls the torque
distribution to the front and rear wheels through the electric control coupling in the rear differential.
ACTIVE TORQUE CONTROL 4WD SYSTEM
1. General
Based on information provided by various sensors, the 4WD ECU controls the amperage that is applied
to the electric control coupling, in order to transmit drive torque to the rear wheels when needed, and in
the amount needed. The following describes the features of the active torque control 4WD system.
Traction performance
Realizes stable start-off and acceleration performance
Driving stability performanceRealizes stable cornering performance
Fuel economyRealizes better fuel economy by transmitting drive torque to the rear
wheels when needed, in the amount needed.
A four-wheel drive lock switch has been provided. This enables the driver to select between the AUTO
and LOCK modes by operating the switch. The system optimally controls the torque distribution to the
front and rear wheels in the respective modes.
Mode
Four-wheel Drive
Lock Switch and
Indicator Light
Outline
AUTOOFF
Optimally distributes drive torque to the front and rear wheels.
Ensures optimal start-off performance during a start-off, based on
information provided by various sensors.
Suppresses the tight corner braking phenomenon* during low-speed
cornering.
Reduces the amount of torque distribution to the rear wheels and
improves fuel economy when the system judges that the vehicle is
traveling steadily.
Disengages the 4WD during braking deceleration.
LOCKON
Distributes the maximum torque limit to the rear wheels.
Distributes the maximum torque limit to the rear wheels during
start-off.
Distributes optimal torque during low-speed cornering.
Disengages the 4WD during braking deceleration.
Disengages the LOCK mode and transfers to the AUTO mode when
the vehicle speed exceeds 40 km / h (25 mph).
*: Tight corner braking phenomenon: a condition in which the brakes are applied due to a rotational difference
between the front and rear wheels, such as during low-speed cornering in the 4WD mode.
The 4WD ECU effects cooperative control with the skid control ECU, in order to control the drive torque
distribution to the front and rear wheels in accordance with information received from the skid control
ECU. These controls ensure a smooth acceleration and driving stability.

SERVICE SPECIFICATIONS – BRAKESS–83
SS
TORQUE SPECIFICATIONS
Brake Pedal
Brake Master Cylinder
Brake Booster
Front Brake
Front Brake Flexible Hose
Rear Brake
Rear Brake Flexible Hose
Part tightened N*m kgf*cm ft.*lbf
Brake pedal support x Body 12.7 130 9
Brake pedal support x Instrument
panel reinforcement25 255 18
Stop light switch 1.5 or less 15 or less 13 in.*lbf or less
Part tightened N*m kgf*cm ft.*lbf
Brake master cylinder x Brake
booster12.5 127 9
Brake master cylinder x Brake
tube (without SST)15.2 155 11
Brake master cylinder x Brake
tube (with SST)14 144 10
Part tightened N*m kgf*cm ft.*lbf
Brake booster x Brake pedal
support12.7 130 9
Push rod clevis lock nut 26 265 19
Part tightened N*m kgf*cm ft.*lbf
Bleeder plug 8.3 85 73 in.*lbf
Cylinder mounting x Knuckle 98 999 72
Cylinder x Cylinder mounting 34.3 350 25
Flexible hose x Cylinder 29.4 300 22
Part tightened N*m kgf*cm ft.*lbf
Flexible hose x Brake cylinder 29.4 300 22
Flexible hose clamp bolt 18.5 189 14
Flexible hose x Brake tube
(without SST)15.2 155 11
Flexible hose x Brake tube (with
SST)14 144 10
Part tightened N*m kgf*cm ft.*lbf
Bleeder plug 8.3 85 73 in.*lbf
Cylinder mounting x Carrier 88 897 65
Cylinder x Cylinder mounting 26.5 270 20
Flexible hose x Cylinder 30.4 310 22
Part tightened N*m kgf*cm ft.*lbf
Flexible hose x Brake cylinder 30.4 310 22
Flexible hose x Brake tube
(without SST)15.2 155 11
Flexible hose x Brake tube (with
SST)14 144 10

AXLE – FRONT AXLE HUBAH–7
AH
REMOVAL
(2005/11-2006/01)
HINT:
• Use the same procedures for the RH side and LH side.
• The procedures listed below are for the LH side.
1. REMOVE FRONT WHEEL
2. DRAIN AUTOMATIC TRANSAXLE FLUID
(a) Drain the automatic transaxle fluid for U140F (see
page AX-147).
(b) Drain the automatic transaxle fluid for U241E (see
page AX-146).
3. DISCONNECT CABLE FROM NEGATIVE BATTERY
TERMINAL
CAUTION:
Wait at least 90 seconds after disconnecting the
cable from the negative (-) battery terminal to
prevent airbag and seat belt pretensioner activation.
4. REMOVE FRONT AXLE HUB NUT
(a) Using SST and a hammer, unstake the staked part
of the nut.
SST 09930-00010
NOTICE:
Loosen the staked part of the nut completely,
otherwise the screw of the drive shaft may be
damaged.
(b) While applying the brakes, remove the lock axle hub
nut.
5. REMOVE FRONT SPEED SENSOR LH (See page BC-
191)
6. REMOVE FRONT DISC BRAKE CYLINDER
ASSEMBLY LH (See page BR-40)
7. REMOVE FRONT DISC (See page BR-42)
8. DISCONNECT TIE ROD END SUB-ASSEMBLY LH
(See page PS-42)
9. DISCONNECT FRONT SUSPENSION NO. 1 LOWER
ARM SUB-ASSEMBLY LH
(a) Remove the bolt and 2 nuts.
(b) Disconnect the lower arm from the ball joint.
C129483E01
C127531

BR–4BRAKE – BRAKE SYSTEM
BR
Noise from brakes1. Front brake pad (cracked, distorted, dirty or glazed)BR-40
2. Rear brake pad (cracked, distorted, dirty or glazed)BR-55
3. Front disc brake pad support plate (loose)BR-40
4. Rear disc brake pad support plate (loose)BR-55
5. Front disc brake cylinder slide pin (worn)BR-40
6. Rear disc brake cylinder slide pin (worn)BR-55
7. Front brake installation bolt (loose)BR-45
8. Rear brake installation bolt (loose)BR-60
9. Front brake disc (scored)BR-40
10. Rear brake disc (scored)BR-55
11. Parking brake shoe return tension spring (faulty)PB-13
12. Front brake anti-squeal shim (damaged)BR-40
13. Rear brake anti-squeal shim (damaged)BR-55
14. Parking brake shoe hold-down spring (damaged)PB-13 Symptom Suspected area See page

GF1A TRANSFER – ACTIVE TORQUE CONTROL 4WD SYSTEMTF–15
TF
PROBLEM SYMPTOMS TABLE
HINT:
• Use the table below to help determine the cause of the
problem symptom. The potential causes of the symptoms
are listed in order of probability in the "Suspected area"
column of the table. Check each symptom by checking the
suspected areas in the order they are listed. Replace parts
as necessary.
• Inspect the fuses and relays related to this system before
inspecting the suspected areas below.
Active torque control 4WD system
HINT:
*:When driving 4WD mode, the vehicle is hard to turn, as if
the brakes were applied, due to the rotational difference
between the front and rear tires while turning.
Symptom Suspected area See page
Phenomenon of tight-corner braking*1.Steering angle sensor circuitTF-27
2.Linear solenoid circuitTF-30
3.4WD control ECU
4WD indicator light remains ON 4WD indicator light circuitTF-36
4WD indicator light does not come ON 4WD indicator light circuitTF-40
The system is in the DTC output mode although
terminals TC and CG of the DLC3 are not short
circuited1.TC and CG terminal circuitTF-42
2.4WD indicator light circuit
The system is not in the DTC output mode although
terminals TC and CG of the DLC3 are not short
circuited1.TC and CG terminal circuitTF-42
2.4WD indicator light circuit

AXLE – FRONT AXLE HUBAH–9
AH
REMOVAL
(2006/01- )
HINT:
• Use the same procedures for the RH side and LH side.
• The procedures listed below are the LH side.
1. REMOVE FRONT WHEEL
2. DRAIN AUTOMATIC TRANSAXLE FLUID
(a) Drain the automatic transaxle fluid for U140F (see
page AX-147).
(b) Drain the automatic transaxle fluid for U241E (see
page AX-146).
(c) Drain the automatic transaxle fluid for U151E (see
page AX-172).
(d) Drain the automatic transaxle fluid for U151F (see
page AX-173).
3. DISCONNECT CABLE FROM NEGATIVE BATTERY
TERMINAL
CAUTION:
Wait at least 90 seconds after disconnecting the
cable from the negative (-) battery terminal to
prevent airbag and seat belt pretensioner activation.
4. REMOVE FRONT AXLE HUB LH NUT
(a) Using SST and a hammer, unstake the staked part
of the nut.
SST 09930-00010
NOTICE:
Loosen the staked part of the nut completely,
otherwise the screw of the drive shaft may be
damaged.
(b) While applying the brakes, remove the lock axle hub
nut.
5. REMOVE FRONT SPEED SENSOR LH (See page BC-
191)
6. REMOVE FRONT DISC BRAKE CYLINDER
ASSEMBLY LH (See page BR-40)
7. REMOVE FRONT DISC (See page BR-42)
8. DISCONNECT TIE ROD END SUB-ASSEMBLY LH
(See page PS-42)
9. DISCONNECT FRONT SUSPENSION NO. 1 LOWER
ARM SUB-ASSEMBLY LH
(a) Remove the bolt and 2 nuts.
(b) Disconnect the lower arm from the ball joint.
C129483E01
C127531

BC–6BRAKE CONTROL – VEHICLE STABILITY CONTROL SYSTEM
BC
SYSTEM DESCRIPTION
1. SYSTEM DESCRIPTION
HINT:
The skid control ECU forms a single unit with the ABS
and TRACTION actuator.
(a) ABS (Anti-lock Brake System):
The ABS helps prevent the wheels from locking
when the brakes are applied firmly or on a slippery
surface.
(1) Operation description:
The skid control ECU detects wheel lock
conditions by receiving vehicle speed signals
from each speed sensor, and sends control
signals to the pump motor and solenoid valve to
prevent wheels from locking by controlling the
brake fluid pressure of each wheel cylinder.
The ABS warning light comes on when the ABS
system malfunctions.
C115099E04

BRAKE CONTROL – VEHICLE STABILITY CONTROL SYSTEMBC–7
BC
(b) EBD (Electronic Brake Force Distribution):
The EBD control utilizes the ABS to create the
proper brake force distribution between the front
and rear wheels in accordance with the driving
conditions and vehicle load. In addition, when the
brakes are applied while cornering, it also controls
the braking forces of the right and left wheels,
helping to maintain vehicle stability.
(1) Operation description:
The skid control ECU receives speed signals
from each speed sensor to detect the slip
conditions of the wheels and sends control
signals to the solenoid.
The solenoid valve controls the brake fluid
pressure of each wheel cylinder and divides the
control power properly between the front and
rear wheels and the right and left wheels.
The brake warning light comes on to indicate
malfunctions in the EBD system.
C115100E05

BRAKE CONTROL – VEHICLE STABILITY CONTROL SYSTEMBC–17
BC
(1) Operation description:
The skid control ECU determines that the
vehicle is in a state in which the AUTO LSD can
operate by using various sensors and switches
to detect the operating conditions of the AUTO
LSD switch, shift position, accelerator pedal, and
brake pedal. When the vehicle is in a state in
which the AUTO LSD can operate, the skid
control ECU effects hydraulic pressure control of
the wheel cylinder at the wheel with the faster
wheel speed so that the wheel speeds of the
right and left drive wheels will become equal.
The slip indicator light blinks and the AUTO LSD
indicator light comes on when the system is
operating. Both the VSC warning light and SLIP
indicator light come on when the AUTO LSD
system malfunctions.
2. COOPERATIVE CONTROL FUNCTION
(a) Description
(1) Braking when Surface Resistance Differs
Between Left and Right Wheels
If the driver suddenly applies the brakes on a
road surface with a considerable difference in
friction coefficient between the right and left
wheels, the difference in the brake force
between the right and left wheels will cause the
vehicle posture to become unstable and create a
yaw movement. In this state, the skid control
ECU controls the VSC to stabilize the vehicle
posture. At the same time, it effects cooperative
control with the EPS to provide steering torque
assist, which facilitates the driver's steering
maneuvers to stabilize the vehicle posture.
(2) Accelerating when Surface Resistance Differs
Between Left and Right Wheels
If the driver suddenly starts off or accelerates on
a road surface with a considerable difference in
friction coefficient between the right and left
wheels, the slippage of a drive wheel will cause
the vehicle posture to become unstable and
negatively affect its acceleration performance. In
this state, the skid control ECU causes the TRC
to control the hydraulic brake of the slipping
drive wheel, and requests the engine ECU to
effect engine output control. At the same time, it
effects cooperative control with the EPS to
provide steering torque assist, which facilitates
the driver's steering maneuvers to stabilize the
vehicle posture.

BRAKE CONTROL – VEHICLE STABILITY CONTROL SYSTEMBC–55
BC
FAIL-SAFE CHART
1. FAIL SAFE OPERATION
• If there is a problem with any sensor signals or
actuator systems, the skid control ECU prohibits the
power supply to the ABS and TRACTION actuator
and informs the ECM of VSC system failure.
The ABS and TRACTION actuator turns off the
solenoids and the ECM s huts off VSC control (traction
control signal) from the skid control ECU accordingly,
the result being that it is as if the ABS, TRC and VSC
systems were not installed.
• ABS control is prohibited, but EBD control continues
as far as possible. If EBD control is impossible, the
BRAKE warning light comes on to warn the driver
(see page BC-44).
• If system components have any malfunctions before
starting control, the operation stops immediately. If
system components have any malfunctions during
control, the control stops gradually so as not to trigger
a sudden change in vehicle conditions.
If it is impossible to control the systems, the warning
light comes on to inform the driver of malfunctions in
the systems (see page BC-44).
HINT:
• If the ABS system malfunctions, the brake system
operates normally without the ABS system.
• If the brake actuator malfunctions, a gradual loss of
brake performance is expected, and ABS system
control is prohibited.
ABS, EBD and BA system
TRC and VSC system:
Malfunction Area Fail-Safe Operation
ABS system ABS, BA, TRC and VSC control prohibited
BA system ABS, BA, TRC and VSC control prohibited
EBD system ABS, EBD, BA, TRC and VSC control prohibited
Malfunction Area Fail-Safe Operation
Engine control system
(TRC and VSC systems)Before control: Disables control
During control: Uses only the brakes to effect control
Brake control system
(VSC system)Before control: Disables control
During control: Uses only the engine to effect control
Brake control system
(TRC system)Before control: Disables control
During control: Disables control (by gradually ending control)