2001 TOYOTA PRIUS change time

NOTICE
When handling supplemental restraint system components (removal,
installation or inspection, etc.), always follow the direction given in the repair
manuals listed above to prevent accidents and supplemental restraint
system malfunction.
CAUTION
When repairing the hybrid vehicle (HV), always follow the direction given in
the repair manual listed above to prevent electrical shock, leakage or
explosion.
2001 PRIUS (EWD414U)
FOREWORD
This wiring diagram manual has been prepared to provide
information on the electrical system of the 2001 PRIUS.
Applicable models: NHW11 Series
For service specifications and repair procedures of the above
models other than those listed in this manual, refer to the
following manuals;
Manual Name
Pub. No.

2001 PRIUS Repair Manual
Volume 1
Volume 2

2001 PRUIS New Car Features
RM778U1
RM778U2
NCF182U
All information in this manual is based on the latest product
information at the time of publication. However, specifications
and procedures are subject to change without notice.

[O]
[P]
[Q]
[R]
[S]
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[U]
[V]
2001 PRIUS (EWD414U)
B HOW TO USE THIS MANUAL
Current is applied at all times through the STOP fuse to TERMINAL 2 of the stop light SW.
When the ignition SW is turned on, current flows from the GAUGE fuse to TERMINAL 8 of the light failure sensor, and also flows
through the rear lights warning light to TERMINAL 4 of the light failure sensor.
STOP LIGHT DISCONNECTION WARNING
When the ignition SW is turned on and the brake pedal is pressed (Stop light SW on), if the stop light circuit is open, the current
flowing from TERMINAL 7 of the light failure sensor to TERMINALS 1, 2 changes, so the light failure sensor detects the
disconnection and the warning circuit of the light failure sensor is activated.
As a result, the current flows from TERMINAL 4 of the light failure sensor to TERMINAL 11 to GROUND and turns the rear lights
warning light on. By pressing the brake pedal, the current flowing to TERMINAL 8 of the light failure sensor keeps the warning
circuit on and holds the warning light on until the ignition SW is turned off.
S6 STOP LIGHT SW
2±1 : Closed with the brake pedal depressed
L4 LIGHT FAILURE SENSOR
1, 2, 7±GROUND : Approx. 12 volts with the stop light SW on
4, 8±GROUND : Approx. 12 volts with the ignition SW at ON position
11±GROUND : Always continuity
: PARTS LOCATION
CodeSee PageCodeSee PageCodeSee Page
C734L436R737
H1736R637S635
: RELAY BLOCKS
CodeSee PageRelay Blocks (Relay Block Location)
118R/B No.1 (Instrument Panel Left)

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ÀÀÀ ÀÀÀ ÀÀÀ
: JUNCTION BLOCK AND WIRE HARNESS CONNECTOR
CodeSee PageJunction Block and Wire Harness (Connector Location)
IB20Instrument Panel Wire and Instrument Panel J/B (Lower Finish Panel)
3C22Instrument Panel Wire and J/B No.3 (Instrument Panel Left Side)
: CONNECTOR JOINING WIRE HARNESS AND WIRE HARNESS
CodeSee PageJoining Wire Harness and Wire Harness (Connector Location)
IE142Floor Wire and Instrument Panel Wire (Left Kick Panel)
BV150Luggage Room Wire and Floor Wire (Luggage Compartment Left)
: GROUND POINTS
CodeSee PageGround Points Location
BL50Under the Left Quarter Pillar
BO50Back Panel Center
: SPLICE POINTS
CodeSee PageWire Harness with Splice PointsCodeSee PageWire Harness with Splice Points
I544Cowl WireB1850Luggage Room Wire
SYSTEM OUTLINE
SERVICE HINTS

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

2001 PRIUS (EWD414U)
6. MANUAL CANCEL CONTROL
When each of the following signals is input during driving with cruise control, the cruise control is released with turning the
cruise control requirement to 0. (The memorized speed is maintained when following signals except the signal, main switch
OFF is input.)
*Stop light switch ON (Pressing the brake pedal)
*Control switch's cancel switch ON
*Main switch OFF
7. AUTO CANCEL FUNCTION
A) The memorized speed is erased and the control is canceled if the following conditions occur. The power indicator blinks
at that time until the main switch is turned ON. The speed control is unavailable unless the main switch is turned ON
again.
*When the stop light switch breaks or short±circuits.
*When sudden change of the running speed signal occur.
B) The memorized speed is erased and the control is canceled if the following conditions occur.
*When the malfunction of the stop light switch input circuit occurs.
*When the running speed becomes slower than 40km/h.
*When the running speed becomes slower than the speed that 16 km/h subtracted from the memorized speed.
8. REGENERATIVE SYSTEM OPERATION
This system operates the motor as a generator to change the kinetic energy of the vehicle into the electricity when accel
pedal release or foot braking controls the vehicle, and store the electricity in the battery.
C14 CRUISE CONTROL SW [COMB. SW]
5±4 : Approx. 1540 W with CANCEL SW on
Approx. 240 W with RES/ACC SW on
Approx. 630 W with SET/COAST SW on
: PARTS LOCATION
CodeSee PageCodeSee PageCodeSee Page
A736H10C37J18A37
A1336H11A37J19B37
A1836H12B37J2137
B836H13E37J22A37
B1136H14D37J23B37
B1538H16A38J24A37
B1638H17B38J25B37
B17A38I9D35J2637
B18B38I10C35J27A37
B1938I11A35J28B37
C334I12B35J3238
C4A34I13E35A38
C5B34I14F35J33B38
C10A36I1537M2A35
C11B36I1738M3B35
C1436J137M4C35
D236J2A37P137
E9C36J3B37S337
E10D36J737S8A39
F1034J8A37S9B39
F12C34J9B37S10C39
F13D34J1137S11D39
F1738J1637S12E39
F1838J1737T437
G137J1837W335
SERVICE HINTS

W 2000 TOYOTA MOTOR CORPORATIONAll rights reserved. This book may not be repro-
duced or copied, in whole or in part, without the
written permission of Toyota Motor Corporation.
First Printing: Apr. 5, 2000 01-000405-00
FOREWORD
To assist you in your sales and service activities, this manual explains the main characteristics of the new PRIUS,
in particular providing a technical explanation of the construction and operation of new mechanisms and new
technology used.
Applicable models: NHW11 series
This manual is divided into 4 sections.
1. Introduction ± Exterior appearance and model code.
2. New Model Outline ± Explanation of the product to give a general understanding of its features.
3. Technical Description ± Technical explanation of the construction and operation of each new system and
component.
4. Appendix ± Major technical specifications of the vehicle.
CAUTION, NOTICE, REFERENCE and NOTE are used in the following ways:
CAUTION
A potentially hazardous situation which could result in injury to people may occur
if instructions on what to do or not do are ignored.
NOTICEDamage to the vehicle or components may occur if instructions on what to do or not
do are ignored.
REFERENCEExplains the theory behind mechanisms and techniques.
NOTENotes or comments not included under the above 3 titles.
For detailed service specifications and repair procedures, refer to the following Repair Manuals:
Manual Name
Pub. No.

2001 PRIUS Repair Manual

2001 PRIUS Electrical Wiring DiagramRM778U
EWD414U
All information contained herein is the most up-to-date at the time of publication. We reserve the right to make
changes without prior notice.

THS (TOYOTA HYBRID SYSTEM)
182TH12
SOCExample of change in SOC
Upper SOC control limit
Control regionTarget SOC
control
Lower SOC control limit
Time
Overcharged region
Overcharged region
39
1. Battery ECU
The battery ECU provides the following functions.
SOC (state of charge) Control
While the vehicle is in motion, the HV battery
undergoes repetitive charging / discharging
cycles, as it becomes discharged by the MG2
during acceleration and charged by the regenera-
tive brake during deceleration. The battery ECU
outputs charge / discharge requests to the HV
ECU so that the SOC can be constantly main-
tained at a center level, by estimating the charg-
ing / discharging amperage.
Cooling Fan Control
To ensure the HV battery's performance considering the heat that is generated in the HV battery during
charging and discharging, the battery ECU controls the operation of the cooling fan.
HV Battery Malfunction Monitoring
This function includes the monitoring of the temperature and the voltage of the battery via the battery ECU.
If a malfunction is detected, the battery ECU protects the HV battery by restricting or stopping the charging
and discharging of the HV battery. In addition, this function illuminates the warning light, outputs DTCs
(Diagnostic Trouble Codes), and stores them in memory. For further details on the DTCs, refer to the 2001
Prius Repair Manual (Pub No. RM778U).

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 ± BRAKES
182CH42While Pressing Locked StateStroke
Reaction Force
of Parking
Brake Cable
182CH43
Press Again During Pedal Return Lift Portion of
Parking Brake Pedal103
3. Operation
During Applying
Pressing the parking brake pedal causes the sector's rachet to engage with the pawl. Then, when the pressure
on the brake pedal is released, the reaction force of the parking brake cable and the force of the pedal return
spring cause the pawl and sector, which remain engaged, to return (only for the stroke). As the result, the
parking brake becomes locked.
At this time, because the relative installed position of the pawl spring changes, the force of the pawl spring
that was applied to the intermediate release lever switches its direction and now pushes the intermediate
release lever down.
During Releasing
When the parking brake pedal is pressed again, as the reaction force of the parking brake cable and the force
of the pedal return spring will not be applied to the pawl, the action of the pawl spring causes the pawl to
lift. As a result, the pawl is released from the sector's ratchet.
Next, when the parking brake pedal returns to its initial point, the lift portion of the parking brake pedal
causes the intermediate release lever to lift. The pawl is then pushed down by the force of the pawl spring
and returns to its initial state.