2001 TOYOTA PRIUS change wheel

2001 PRIUS (EWD414U)
TOYOTA HYBRID SYSTEM
FEATURES OF TOYOTA HYBRID SYSTEM
This system controls the following modes in order to achieve the most efficient operations to match the driving conditions.
(1) Supply of electrical power from the HV battery to motor generator no.2 provides force to drive the wheels.
(2) While the tires are driven by the engine via the planetary gears, motor generator no.1 is driven via the planetary gears to
supply electricity to motor generator no.2 to drive the wheels.
(3) When the vehicle is decelerating, kinetic energy from the wheels is recovered and converted into electrical energy and
used to recharge the HV battery by means of motor generator no.2.
The hybrid vehicle control ECU switches between these modes (1, 2, 1+2, or 3) according to the driving conditions.
However, when the state of charge of the HV battery is low, the HV battery is charged by the engine by turning motor
generator no.1.
CRUISE CONTROL OPERATION
Cruise control is the speed control device, which sets the desired speed by just operating the switch on the control panel
without pressing the accelerator pedal. This device is used when you would like to drive the vehicle at the fixed speed.
1. SET CONTROL
If you operate the SET/COAST switch when driving (The available range of set speed: between about 40 and 200 km/h) with
the main switch is ON (When power indicator comes on), the device memorizes vehicle's speed when switch is off and
controls the fixed speed.
2. SET SPEED CONTROL
This device compares the vehicle's running speed and the memorized speed, and controls the driving power of the motor
and the engine by calculating the cruise control requirements so that both speed become equivalent.
3. COAST CONTROL
If the SET/COAST switch is continued to be ON during the running with the cruise control, the device recognizes the cruise
control requirement is at 0 and decelerates the vehicle's speed. Then the device memorizes the speed when the switch is off
in order to control the fixed speed.
In each time you operate SET/COAST switch momentarily (For about 0.5 second), the memorized speed is decreased in
about 1.5 km/h. However, in case of the tap±down operation with more than 5±km/h gap between the memorized speed and
vehicle's running speed, the device memorizes the vehicle's speed when the switch is off and controls the fixed speed.
4. ACCEL CONTROL
If the RESUME/ACCEL switch is continued to be ON during the running with the cruise control, the device recognizes the
cruise control is on the acceleration side and accelerates the vehicle's speed. Then the running speed when the switch is off
is memorized to control the fixed speed.
In each time you operate RESUME/ACCEL switch momentarily (For about 0.5 second), the memorized speed is increased
in about 1.5 km/h. However, if there is more than 5±km/h gap between the memorized speed and vehicle's running speed,
this operation does not change the memorized speed. (Tap±up operation is not available.)
5. RESUME CONTROL
If the running speed is faster than the low speed limit after the cruise control is canceled manually, the fixed speed is
controlled by the OFF±ON operation of RESUME/ACCEL switch, so that the vehicle's speed returns to the memorized
speed at the time the cruise control is released.
SYSTEM OUTLINE

CHASSIS ± SUSPENSION AND AXLES
181CH24 181CH23
StraightlineNegative
Camber
Cornering
182CH31
Bound StopperRebound Stopper
Upper
Insulator
Stopper
Clearance
94
Negative Camber
The front suspension adopts negative camber to reduce the ground contact camber angle of the outer wheel
at the time of turning (cornering), which is caused when the vehicle posture changes during cornering, thus
realizing excellent cornering performance.
Suspension Upper Support and Dust Cover
The upper support optimizes the characteris-
tics of the rubber mount. Also, a rebound stop-
per has been provided to ensure riding com-
fort, drivability, and stability.
A bound stopper made of urethane has been
adopted. By optimizing the stopper character-
istics and the clearance, excellent riding com-
fort and a high level of roll rigidity have been
achieved.
An upper insulator that is integrated with the
dust boot has been adopted.

CHASSIS ± SUSPENSION AND AXLES
165CH48
Center of Bushing
BOUND
Center of Bushing
Camber Change Rate a/L
Camber Change Rate 100%a
L
Instantaneous
Center of
Right Axle
REBOUND
An alignment change that
is very close to that of the
semi-trailing suspension is
effected.
98
Toe and Camber Change
In the torsion beam type suspension, the camber angle and the toe change differ between the same direction
stroke case and the opposite direction stroke case, offering both straightline stability and excellent cornering
stability.
1) Same Direction Stroke Case
Similar to the full-trailing arm type suspension, the axis that joins the center of the right and left trailing
arm bushings is the center of the movement.
2) Opposite Direction Stroke Case
During opposite direction stroke case, or if a difference in suspension travel is created between the right
and left wheels, the torsion beam twists with its shearing center as the center of its rotation.
Also, camber changes in relation to the suspension travel are determined by the ratio of the distance be-
tween the No.1 trailing arm bushing and the axle center and the shearing center (`a' in the Fig. below)
and distance between the No.1 trailing arm bushing and the axle beam (`L' in the Fig. below).
Consequently, through the optimal allocation of the axle beam, the changes in the camber angle in rela-
tion to the suspension travel have been optimized, thus ensuring excellent cornering performance.
Shock Absorber

Low-pressure (N
2) gas sealed shock absorbers that offer stable dampening force characteristics without
causing cavitation have been adopted.

The dampening force characteristics of the shock absorbers have been optimized to achieve excellent
riding comfort, drivability, and stability.

CHASSIS ± BRAKES105
4. Function of Main Components
ComponentsFunction
ABS Warning
LightLights up to alert the driver when the brake ECU detects the
malfunction in the ABS.
Combination
Meter
Brake System

Lights up together with the ABS warning light to alert the driver
when the brake ECU detects the malfunction not only in the ABS
but also in the EBD controlBrake System
Warning Lightbut also in the EBD control.

Lights up to alert the driver when the malfunction occurs in the
brake system.
Stop Light SwitchDetects the brake depressing signal.
Brake Warning BuzzerEmits a continuous sound to inform the driver that the ABS ECU
detects the malfunction in the hydraulic brake booster.
Speed SensorsDetect the wheel speed of each of the four wheels.
Brake ECU

Processes various sensor signals, regenerative brake signals, to
execute control of the ABS control, EBD control, regenerative
coordination control and hydraulic brake booster.

Communicates control data with the HV ECU.
HV ECUMaintains serial communication with the brake ECU to exchange
regenerative coordination control signals.
Hydraulic Brake Booster
Assists with the pedal effort applied to the brake pedal.

Supplies hydraulic pressure.
Brake ActuatorControls the brake fluid pressure to each brake wheel cylinder by
signals from the brake ECU.
Solenoid RelaySupplies power to the ABS's solenoid valve's in the brake actuator.
Pump Motor RelaysControl the pump motor operation in the hydraulic brake booster.

CHASSIS ± BRAKES
Battery
Acceptance
Capacity
182CH58
Braking
Force
Regenerative
Braking ForceHydraulic
Braking Force
Vehicle SpeedRegenerative
Braking ForceHydraulic
Braking Force
Time
Changes in Regenerative Braking Force Changes in Braking Force Apportionment
Braking
Force
Driver's DemandDriver's Demand 11 8
2) Regenerative Brake Cooperative Control
a. General
The regenerative brake cooperative control uses the switching valves and linear solenoid valves to regu-
late the hydraulic pressure that is supplied to the wheel cylinders. It also operates cooperatively with
the regenerative braking force that is generated in the MG2 in accordance with the master cylinder pres-
sure.
b. Apportioning of the Brake Force
The apportioning of the brake force between the hydraulic brake and the regenerative brake varies by
the vehicle speed and time.
The apportioning of the brake force between the hydraulic brake and the regenerative brake is con-
trolled so that the total brake force of the hydraulic brake and the regenerative brake matches the brake
force that the driver requires.

Imagery Drawing 
c. Operation
Regenerative brake cooperative control is executed when the vehicle is driven in the shift position ªDº
or ªBº.
The master cylinder pressure that is generated when the driver presses on the brake pedal is detected
by the pressure sensor, and the brake ECU calculates the brake force request factor. A portion of the
brake force request factor is transmitted to the HV ECU in the form of a regenerative brake activation
request factor. The HV ECU executes generative braking by commanding the electric motor to generate
negative torque.
The brake ECU controls the opening of the linear solenoid valves, which are used for increasing / de-
creasing the hydraulic pressure, to regulate the wheel cylinder hydraulic pressure in relation to the mas-
ter cylinder hydraulic pressure, thus compensating for the brake force that is not provided sufficiently
by the regenerative brake.
While the regenerative brake cooperative control is being prohibited due to an abnormality in the sys-
tem, or when the shift lever is in a position other than D or B, the regenerative braking force is not gener-
ated. At this time, only the hydraulic braking force is applied by turning ON (opening) the linear sole-
noid valve SLA and turning OFF (closing) the SLR.

CHASSIS ± STEERING
182CH73
Contact 1 Resistor 1
Upward
Resistor 2
DownwardContact 2
Contacts Torque
Sensor
Resistor
182CH74
Resistor
Basic
Position
Contact
Straightline 126
4) Torque Sensor
A torque sensor that detects the torque that is input by the steering wheel has been mounted on the pinion
shaft. The torque sensor has been integrated with the pinion shaft, and the pinion shaft's input and output
shafts are linked via the torsion bar. Resistors for the torque sensor are mounted on the input shaft of the
pinion shaft, and contacts for the torque sensor are mounted on the output shaft of the pinion shaft. Oper-
ating the steering wheel causes the torsion bar to twist, creating a displacement between the pinnion
shaft's input and output. Two systems of torque sensors detect this displacement in the form of voltage
changes, which are then output to the EMPS ECU.
i) Straightline Driving
If the vehicle is driven straight and the driv-
er does not turn the steering, torque is not
generated in the pinion shaft's input shaft.
Thus, the torsion bar does not twist, and no
changes in resistance occur in the torque
sensor.

MA02F±02
MA±2
± MAINTENANCEINSIDE VEHICLE
55 Author: Date:
2001 PRIUS (RM778U)
INSIDE VEHICLE
GENERAL MAINTENANCE
These are maintenance and inspection items which are considered to be the owner's responsibility.
They can be done by the owner or they can have them done at a service shop.
These items include those which should be checked on a daily basis, those which, in most cases, do not
require (special) tools and those which are considered to be reasonable for the owner to do.
Items and procedures for general maintenance are as follows.
1. GENERAL NOTES

Maintenance items may vary from country to country. Check the owner's manual supplement in which
the maintenance schedule is shown.

Every service item in the periodic maintenance schedule must be performed.

Periodic maintenance service must be performed according to whichever interval in the periodic main-
tenance schedule occurs first, the odometer reading (miles) or the time interval (months).

Maintenance service after the last period should be performed at the same interval as before unless
otherwise noted.
2. LIGHTS
(a) Check that the headlights, stop lights, taillights, turn signal lights, and other lights are all working.
(b) Check the headlight aim.
3. WARNING LIGHTS AND BUZZERS
Check that all warning lights and buzzers function properly.
4. HORN
Check that it is working.
5. WINDSHIELD GLASS
Check for scratches, pits or abrasions.
6. WINDSHIELD WIPER AND WASHER
(a) Check operation of the wipers and washer.
(b) Check that the wipers do not streak.
7. WINDSHIELD DEFROSTER
Check that air comes out from the defroster outlet when operating the heater or air conditioner.
8. REAR VIEW MIRROR
Check that it is mounted securely.
9. SUN VISORS
Check that they move freely and are mounted securely.
10. STEERING WHEEL
Check that it has the specified freeplay. Be alert for changes in steering condition, such as hard steering,
excessive freeplay or strange noises.
11. SEATS
(a) Check that the seat adjusters operate smoothly.
(b) Check that all latches lock securely in any position.
(c) Check that the head restraints move up and down smoothly and that the locks hold securely in any
latch position.
(d) For fold±down seat backs, check that the latches lock securely.
12. SEAT BELTS
(a) Check that the seat belt system such as the buckles, retractors and anchors operate properly and
smoothly.
(b) Check that the belt webbing is not cut, frayed, worn or damaged.

± DIAGNOSTICSHV BATTERY CONTROL SYSTEM
DI±341
2001 PRIUS (RM778U) 4/27/01
DTC P3011±P3029 Battery Block # Malfunction
CIRCUIT DESCRIPTION
Internal resistance of each battery module is measured, detecting battery deterioration for each block, 1 to
19. Nineteen blocks of battery modules are arranged in the order of 1 to 19 from the ECU side.
DTC No.DTC Detecting ConditionTrouble Area
P3011±P3029Battery internal resistance is abnormal.
Battery ECU

Battery pack
INSPECTION PROCEDURE
1 Are there any other codes (besides DTC P3011±P3029) being outputs?
YES Go to relevant DTC chart.
NO
2 Check that the block voltage during charging/ discharging.
PREPARATION:
(a) To ensure safety, conduct this test in a wide, clear level area which provides good traction.
(b) Turn ON the ºREADYº light.
(c) Warm up the engine and turn off the A/C switch.
(d) Fully apply the parking brake and chock the 4 wheels.
(e) Connect a TOYOTA hand±held tester to DLC3 and select HV BATTERY and then CURRENT DATA.
(f) Show voltage of the block corresponding to the DTC and other block (any block except the above±
mentioned block).
CHECK:
(a) Keep your left foot pressed firmly on the brake pedal and shift into the R position.
(b) Confirm the engine stopped in the R position. Step on the accelerator pedal until the engine starts,
stepping on the brake pedal firmly.
(c) Release the accelerator pedal when the engine starts. At the same time, monitor the change of the
voltage before engine starting (during discharging) and after engine starting (during charging).
DI82C±01