2006 TOYOTA RAV4 Brake system

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.

CHASSIS - 4WD SYSTEM
01MCH09Y
Electric Control Coupling
4WD ECU
Four-wheel Drive
Lock Switch
4WD LOCK
Indicator Light
4WD Warning
LightECM
Skid Control ECU
Main Body ECU
Ya w R a t e &
Deceleration Sensor
Steering Angle
SensorThrottle Position Sensor
Crankshaft Position Sensor
Park / Neutral Position
Switch
Speed Sensors
Stop Light Switch
Ambient Temperature
Sensor
Parking Brake Switch
CANH,
CANLCH-67
2. System Diagram

CHASSIS - 4WD SYSTEM
01NCH36Y
Skid Control ECU
Electric Control Coupling
ECM Ambient Temperature
Sensor
Main Body ECUSteering Angle
Sensor
Four-wheel Drive
Lock Switch
4WD ECU
Parking Brake
Switch Stop Light Switch
Yaw Rate & Deceleration
Sensor DLC3 CH-68
3. Layout of Main Components

CHASSIS - 4WD SYSTEMCH-69
4. Function of Main Components
ComponentFunction
Combination
4WD LOCK
Indicator LightIlluminates to inform the driver of the 4WD LOCK mode control.Combination
Meter4WD
Warning LightIlluminates to warn the driver of a malfunction in the 4WD system.
Speed Sensor (4)Detects the wheel speed of each 4 wheel.
Steering Angle SensorDetects the direction and angle of the steering wheel.
Yaw Rate & Deceleration SensorDetects the vehicle’s longitudinal and lateral acceleration.
Crankshaft Position SensorDetects the engine speed and outputs it to the ECM.
Accelerator Pedal Position SensorDetects the accelerator pedal position and outputs it to the ECM.
Throttle Position SensorDetects the throttle valve position and outputs it to the ECM.
Park / Neutral Position SwitchDetects the neutral position of the transaxle and outputs it to the
ECM.
Stop Light SwitchDetects the brake pedal depressing signal.
Parking Brake SwitchDetects when the parking brake lever is pulled up.
Four-wheel Drive Lock SwitchSwitches between the AUTO and LOCK modes.
4WD ECU
Controls the amperage that is applied to the electromagnetic
solenoid of the electric control coupling based on the signals
provided by the sensors in order to optimally distribute drive torque
in accordance with driving conditions.
ECMOutputs signals such as the shift position signal, throttle position
signal, and crankshaft position signal to the 4WD ECU.
Skid Control ECUOutputs signals such as the vehicle speed signal and deceleration
signal to the 4WD ECU.
Electric Control CouplingDistributes drive torque in accordance with the amperage applied
by the 4WD ECU.

MAINTENANCE – UNDER HOODMA–7
MA
GENERAL MAINTENANCE
(2006/01- )
1. GENERAL NOTES
• Maintenance requirements vary depending on the
country.
• Check the maintenance schedule in the owner's
manual supplement.
• Following the maintenance schedule is mandatory.
• Determine the appropriate time to service the vehicle
using either miles driven or time elapsed, whichever
reaches the specification first.
• Maintain similar intervals between periodic
maintenance, unless otherwise noted.
• Failing to check each vehicle part could lead to poor
engine performance and increase exhaust emissions.
2. WINDSHIELD WASHER FLUID
(a) Check that there is sufficient fluid in the tank.
3. ENGINE COOLANT LEVEL
(a) Check that the coolant level is between the "FULL"
and "LOW" lines on the see-through reservoir.
4. RADIATOR AND HOSES
(a) Check that the front of the radiator is clean and not
blocked by leaves, dirt or bugs.
(b) Check the hoses for cracks, kinks, rot or loose
connections.
5. BATTERY ELECTROLYTE LEVEL
(a) Check that the electrolyte level of all the battery
cells is between the upper and lower level lines on
the case.
HINT:
If the electrolyte level is difficult to see, lightly shake
the vehicle.
6. BRAKE FLUID LEVEL
(a) Check that the brake fluid levels are near the upper
level lines on the see-through reservoirs.
7. ENGINE DRIVE BELT
(a) Check the drive belt for fraying, cracks, wear or
oiliness.
8. ENGINE OIL LEVEL
(a) Check the level on the dipstick with the engine
stopped.
9. AUTOMATIC TRANSAXLE FLUID LEVEL
10. EXHAUST SYSTEM
(a) Check for unusual exhaust sounds or abnormal
exhaust fumes. Inspect the cause and repair it.
Type See procedures
U151E See page AX-126
U151F See page AX-126

BC–4BRAKE CONTROL – VEHICLE STABILITY CONTROL SYSTEM
BC
SYSTEM DIAGRAM
C132092E03

BRAKE CONTROL – VEHICLE STABILITY CONTROL SYSTEMBC–5
BC
C136077E01

BRAKE – BRAKE SYSTEMBR–3
BR
PROBLEM SYMPTOMS TABLE
(2005/11-2006/01)
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.
Brake system
Symptom Suspected area See page
Low pedal or spongy pedal1. Fluid leaks in brake system -
2. Air in brake systemBR-6
3. Front brake piston seals (worn or damaged)BR-40
4. Rear brake piston seals (worn or damaged)BR-55
5. Brake master cylinder (faulty)BR-21
6. Booster push rod (adjustment necessary)BR-24
Brake drag1. Brake pedal free play (minimum)BR-14
2. Parking brake lever travel (adjustment necessary)PB-1
3. Parking brake cable (sticking)PB-8
4. Parking brake shoe clearance (adjustment necessary)PB-17
5. Front brake pad (cracked or distorted)BR-40
6. Rear brake pad (cracked or distorted)BR-55
7. Parking brake lining (cracked or distorted)PB-13
8. Front brake piston (stuck or frozen)BR-40
9. Rear brake piston (stuck or frozen)BR-55
10. Parking brake shoe return tension springPB-13
11. Booster push rod (adjustment necessary)BR-24
12. Vacuum leaks in booster systemBR-29
13. Brake master cylinder (faulty)BR-21
Brake pull1. Front brake piston (stuck or frozen)BR-40
2. Rear brake piston (stuck or frozen)BR-55
3. Front brake pad (oily, cracked or distorted)BR-40
4. Rear brake pad (oily, cracked or distorted)BR-55
5. Parking brake lining (oily, cracked or distorted)PB-13
6. Front brake disc (uneven wear)BR-40
7. Rear brake disc (uneven wear)BR-55
Hard pedal but braking inefficient1. Front brake pad (worn, cracked, distorted, oily or glazed)BR-40
2. Rear brake pad (worn, cracked, distorted, oily or glazed)BR-55
3. Parking brake lining (worn, cracked, distorted, oily or
glazed)PB-13
4. Front brake disc (uneven wear)BR-40
5. Rear brake disc (uneven wear)BR-55
6. Booster push rod (adjustment necessary)BR-24
7. Vacuum leaks in booster systemBR-29