2006 TOYOTA RAV4 sensor

TIRE AND WHEEL – TIRE PRESSURE WARNING SYSTEMTW–27
TW
C2165/65 Abnormal Temperature Inside ID1
Tire- Tire
- Tire pressure warning valve and
transmitterTW-36
C2166/66 Abnormal Temperature Inside ID2
Tire- Tire
- Tire pressure warning valve and
transmitterTW-36
C2167/67 Abnormal Temperature Inside ID3
Tire- Tire
- Tire pressure warning valve and
transmitterTW-36
C2168/68 Abnormal Temperature Inside ID4
Tire- Tire
- Tire pressure warning valve and
transmitterTW-36
C2169/69 Abnormal Temperature Inside ID5
Tire- Tire
- Tire pressure warning valve and
transmitterTW-36
C2171/71 Transmitter ID not Registered in
Main Mode- Tire pressure warning ECUTW-39
C2176/76 Receiver Error - Tire pressure warning and
receiver
- Tire pressure warning ECU
- Wire harnessTW-41
C2181/81 Transmitter ID1 not Received
(Test Mode DTC)- Tire pressure warning valve and
transmitter
- Tire pressure antenna and
receiver
- Tire pressure warning ECU
- Wire harnessTW-28
C2182/82 Transmitter ID2 not Received
(Test Mode DTC)- Tire pressure warning valve and
transmitter
- Tire pressure antenna and
receiver
- Tire pressure warning ECU
- Wire harnessTW-28
C2183/83 Transmitter ID3 not Received
(Test Mode DTC)- Tire pressure warning valve and
transmitter
- Tire pressure antenna and
receiver
- Tire pressure warning ECU
- Wire harnessTW-28
C2184/84 Transmitter ID4 not Received
(Test Mode DTC)- Tire pressure warning valve and
transmitter
- Tire pressure antenna and
receiver
- Tire pressure warning ECU
- Wire harnessTW-28
C2185/85 Transmitter ID5 not Received
(Test Mode DTC)- Tire pressure warning valve and
transmitter
- Tire pressure antenna and
receiver
- Tire pressure warning ECU
- Wire harnessTW-28
C2191/91 Vehicle Speed Signal Error (Test
Mode DTC)- Vehicle speed sensor
- Tire pressure warning ECU
- Combination meter
- Wire harnessTW-44 DTC No. Detection Item Trouble Area See page

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

BC–8BRAKE CONTROL – VEHICLE STABILITY CONTROL SYSTEM
BC
(c) BA (Brake Assist):
The primary purpose of the brake assist system is to
provide auxiliary brake force to assist drivers who
cannot generate a large enough brake force during
emergency braking, thus helping to maximize the
vehicle's braking performance.
(1) Operation description:
The skid control ECU receives speed signals
from each speed sensor and the fluid pressure
signal from the master cylinder pressure sensor
to determine whether brake assist is necessary.
If brake assist is deemed necessary, the skid
control ECU sends control signals to the pump
motor and solenoid. The pump and the solenoid
valve then control the pressure applied to each
wheel cylinder. The ABS warning light comes on
to indicate malfunctions in the BA (brake assist)
system.
w/ 16-inch disc: The brake warning light and
ABS warning light come on to indicate
malfunctions in the BA system.
C135908E01

BC–10BRAKE CONTROL – VEHICLE STABILITY CONTROL SYSTEM
BC
(1) Operation description:
The skid control ECU detects the vehicle's slip
condition by receiving signals from each speed
sensor and the ECM via CAN communication.
The skid control ECU controls engine torque
with the ECM via CAN communication and
brake fluid pressure through the pump and
solenoid valve. The slip indicator light blinks
when the system is operating.
for 4WD: The VSC warning light comes on when
the TRC system malfunctions.
for 2WD: The VSC warning light and SLIP
indicator light comes on when the TRC system
malfunctions.

BC–12BRAKE CONTROL – VEHICLE STABILITY CONTROL SYSTEM
BC
(1) Operation description:
The skid control ECU determines the vehicle
condition by receiving signals from the speed
sensor, the yaw rate and deceleration sensor
and the steering sensor. The skid control ECU
controls engine torque with the ECM via CAN
communication and brake fluid pressure through
the pump and solenoid valve. The slip indicator
light blinks and the skid control buzzer sounds
when the system is operating.
for 4WD: The VSC warning light comes on when
the TRC system malfunctions.
for 2WD: The VSC warning light and slip
indicator light come on when the TRC system
malfunctions.
(f) Downhill Assist Control:
When the downhill assist control switch is pressed
with the shift lever on L or R range and the
accelerator and brake pedals not depressed,
downhill assist control is activated. When activated,
4-wheel hydraulic pressure control occurs in order
to maintain a constant low vehicle speed without
causing the wheels to become locked. Thus, the
vehicle can descend a steep hill in a stable manner.
HINT:
• Depressing the accelerator and brake pedal
cancels control of the downhill assist control.
• Downhill assist control begins operating when
driving down on a slope at a speed of 25 km/h
(16 mph) or less with the engine brake applied.

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.

BC–18BRAKE CONTROL – VEHICLE STABILITY CONTROL SYSTEM
BC
(3) Front Wheel Skid Tendency
When the skid control ECU determines that
there is a front wheel skid tendency, it controls
the VSC to dampen the front wheel skid. 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. To prevent
excessive steering maneuvers, it provides a
steering torque assist. This assist increases the
resistance to counter the driver's steering effort,
if the driver turns the steering wheel excessively.
(4) Rear Wheel Skid Tendency
When the skid control ECU determines that
there is a rear wheel skid tendency, it controls
the VSC to dampen the rear wheel skid. At the
same time, it effects cooperative control with the
EPS to provide steering torque assist, which
facilitates the driver's steering maneuvers in the
direction to correct the rear wheel skid.
(5) Acceleration During Cornering
A sudden acceleration of the vehicle during
cornering may cause a drive wheel to freewheel,
which could cause the front wheels or rear
wheels to skid. If the skid control ECU
determines that there is freewheeling of a drive
wheel, a front wheel skid tendency, or a rear
wheel skid tendency, it effects cooperative
control with the 4WD system to optimally control
the drive torque distribution to the front and rear
wheels. Furthermore, it controls the TRC and
the VSC as needed to ensure driving stability
and acceleration performance.
(b) Operation
The operation of the solenoid valves under the
cooperative control is the same as the TRC or VSC
operation.
3. ABS WITH EBD, BA, TRC AND VSC OPERATION
(a) The skid control ECU calculates vehicle stability
tendency based on the signals from the 4 wheel
speed sensors, the yaw rate and deceleration
sensor and the steering sensor. In addition, it
evaluates the results of the calculations to
determine whether any control actions (control of
the engine output torque by electronic throttle
control and of the brake fluid pressure by the ABS
and TRACTION actuator) should be implemented.
(b) The slip indicator blinks and the skid control buzzer
sounds to inform the driver that the VSC system is
operating. The slip indicator also blinks when
traction control is operating, and the operation being
performed is displayed.