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.
BODY ELECTRICAL ± ACCESSORIES
182BE41
RRP DBody
ECUUARTPower
Window
Master
SwitchDoor Control
Switch (Manual)
Door Control
Switch (Key-linked)
169BE10
Key Unlock
Warning SwitchDoor Courtesy
Switch
Door Lock
MotorsBody
ECU
Serial Data Link
Wireless Door
Control Receiver
Horn
RelayHeadlight
RelayTaillight
RelayTransmitter183
DOOR LOCK CONTROL SYSTEM
The door lock control system has the following features:
This system has a ªkey-linked lock and unlockº, ªkey-confine preventionº and ªmanual unlock prohibi-
tionº functions.
A 2-step unlock function is provided to unlock the driver's door by turning the key cylinder first and to
unlock passenger's door by turning it the second time.
The control of this system is effected by the body ECU. The door lock control signal from the driver's door
is transmitted from the power window master switch to the body ECU through the UART (Universal
Asynchronous Receiver Transmitter).
If you unlock using the ignition key from the conditions in which all the doors are locked, the dome light
will be lighted.
System Diagram
WIRELESS DOOR LOCK REMOTE CONTROL SYSTEM
The wireless door lock remote control system has the following features:
In this system, the wireless door control receiver performs the code identification process and the body
ECU effects the door lock control. Serial data link is provided for communication between the wireless
door control receiver and the body ECU.
A key-holder type transmitter has been adopted, and it contains the following three switches: the door lock
switch, door unlock switch, and panic switch.
A rolling code system, in which the signal configuration changes each time when a signal is transmitted
by the transmitter, has been adopted.
Panic alarm operation has been adopted.
The verification light function has been adopted. When the transmitter is used to lock or unlock the doors,
this function flashes the taillights to inform that the operation has been completed. However, at the time
of unlocking, the dome light will be lighted.
BODY ELECTRICAL ± ACCESSORIES
Non-Alert State
Alert State
Alert Preparation State
Alarm State
Condition (3) Condition (1)
Condition (5) Condition (2)
Condition (6)
Condition (4)
Condition (5) 186
List of Input / Output Signals
Terminal
NameOutlineTerminal
NameOutline
DKLDriver's door key lock signalLCTYRear left door courtesy switch status
signal
DKULDriver's door key unlock signalHCTYHood courtesy switch status signal
LSWDDriver's door lock position switch
signalLUGLuggage compartment door courtesy
switch status signal
IGIgnition key switch status signalPKLFront passenger door key lock signal
LSWPFront passenger door lock position
switch signalPKULFront passenger door key unlock
signal
LSRRear left door lock position switch
signalHRLYOutput signal to headlight relay
KSWIgnition key cylinder's key
presence / absence signalTRLYOutput signal to taillight relay
DCTYDriver's door courtesy switch status
signalHROutput signal to vehicle horn relay
PCTYFront passenger door courtesy switch
status signalMPXMultiplex Communication (BEAN)
RCTYRear right door courtesy switch
status signalINDOutput signal to security indicator
2. Operation
Non-Alert State: When the security function is inactive
Without having the ignition key in the ignition key cylinder, if any one of the conditions listed below exists,
the system transfers to the alert preparation state.
Condition (1)
When the doors, engine hood, and luggage compartment door are all closed, the ignition key is used to
lock all doors.
When the doors, engine hood, and luggage compartment door are all closed, the wireless door lock re-
mote control system is used to lock all doors.
When all doors are locked, if any door, engine hood, or luggage compartment door is changed from ªcloseº
to ªopenº, and ªcloseº again, all doors, engine hood, and luggage compartment door will be locked.
Alert Preparation State: a delay time until the alert state
The system transfers to the alert state if the condition (2) listed below is met, and to the non-alert state if one
of the conditions (3) is met.
BODY ELECTRICAL ± ACCESSORIES187
Condition (2)
When the doors, engine hood, and luggage compartment door are all closed and locked, and 30 seconds
have elapsed.
Condition (3)
When one of the doors, engine hood, or luggage compartment door is changed from ªcloseº to ªopenº.
When one of the doors, engine hood, or luggage compartment door is changed from ªlockº to ªunlockº.
When the ignition key is inserted in the ignition key cylinder.
When a terminal is disconnected from the battery and re-connected.
Alert State: a state in which attempted theft can be detected
The system transfers to the alarm state if any one of the conditions (4) listed below is met, or to the non-alert
state if any one of the conditions (5) is met.
Condition (4)
Any door, engine hood, or luggage compartment door is opened.
The ignition key or the wireless door lock remote control system other than the transmitter is used for
unlocking.
The luggage compartment door is opened with something other than the ignition key.
The engine hood is opened.
A terminal is disconnected from the battery and re-connected.
The wiring harness is directly connected as if to turn the ignition switch ON.
Condition (5)
The ignition key is used to unlock the doors or the luggage compartment door.
The transmitter of the wireless door lock remote control system is used to unlock the doors.
The ignition key is inserted in the ignition key cylinder and turned until the ignition switch is ON.
Alarm State: a state in which attempted theft can be detected
When an attempted theft is detected, the system sounds the vehicle's horn and the security horn, flashes
the headlights, taillights, and hazard lights, and illuminates the interior light to alert the people in the area.
If any one of the doors is unlocked, and the ignition key is not inserted in the ignition key cylinder, the
system forcefully locks the doors once.
The system transfers to the alert state if the condition (6) described below is met, or, when the system is
in the alarm state, it transfers to the non-alert state if any one of the conditions (5) described above is met.
At this time, the taillights are illuminated for 2 seconds to inform the driver that an attempted theft has been
detected.
Condition (6)
After approximately 60 seconds of the alarm time have elapsed.
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.
A00310
E1
Engine Coolant Temp.
Sensor
2
1ECM
W
BR14
E8
E8185V
THW
E2
E1 R DI±32
± DIAGNOSTICSENGINE
2001 PRIUS (RM778U)
DTC P0115 Engine Coolant Temp. Circuit Malfunction
CIRCUIT DESCRIPTION
A thermistor built into the engine coolant temp. sensor changes the resistance value according to the engine
coolant temp.
The structure of the sensor and connection to the ECM is the same as in the intake air temp. circuit malfunc-
tion shown on page DI±28.
If the ECM detects the DTC P0115, it operates fail safe function in which the engine coolant temperature
is assumed to be 80°C (176°F).
DTC No.Detection ItemTrouble Area
P0115Open or short in engine coolant temp. sensor circuit
Open or short in engine coolant temp. sensor circuit
Engine coolant temp. sensor
ECM
HINT:
After confirming DTC P0115, use the OBD II scan tool or TOYOTA hand±held tester to confirm the engine
coolant temp. from ºCURRENT DATAº.
Temp. DisplayedMalfunction
±40°C (±40°F)Open circuit
140°C (284°F) or moreShort circuit
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT:
If DTC P0110, P0115 and P0120 are output simultaneously, E2 (sensor ground) may be open.
Read freeze frame data using TOYOTA hand±held tester or OBD II scan tool. Because freeze frame
records the engine conditions when the malfunction is detected, when troubleshooting it is useful for
determining whether the vehicle was running or stopped, the engine warmed up or not, the air±fuel
ratio lean or rich, etc. at the time of the malfunction.
DI6UY±02
DI±36
± DIAGNOSTICSENGINE
2001 PRIUS (RM778U)
DTC P0116 Engine Coolant Temp. Circuit Range/
Performance Problem
CIRCUIT DESCRIPTION
Refer to DTC P0115 on page DI±32.
DTC No.DTC Detecting ConditionTrouble Area
When the engine starts, the water temp. is ±7°C (20°F) or
less. And, 20 min. or more after the engine starts, the engine
temp. sensor value is 5°C (41°F) or less (2 trip detection logic)
When the engine starts, the water temp. is between ±7°C
(20°F) and 10°C (50°F). And, 5 min. or more after the engine
starts, the engine coolant temp. sensor value is 5°C (41°F) or
less. (2 trip detection logic)
P0116When the fluctuations in the engine coolant tempeerature are
within 3 °C (37 °F)before and afrer the follwing conditions are
met:
1. IDL OFF time 250 sec.
2. Vehicle speed change of 30 km/h (19 mph) or more occurs
10 times or more.
3. 35 °C (95 °F) Engine coolant temperature when the
ignition switch is turned ON < 60 °C (140 °F)
4. Intake air temperature after starting the engine ±6.7 °C
(20 °F)Engine coolant temp. sensor
Cooling system
INSPECTION PROCEDURE
HINT:
If DTC P0115 and P0116 are output simultaneously, engine coolant temp. sensor circuit may be open.
Perform troubleshooting of DTC P0115 first.
Read freeze frame data using TOYOTA hand±held tester or OBD II scan tool. Because freeze frame
records the engine conditions when the malfunction is detected, when troubleshooting it is useful for
determining whether the vehicle was running or stopped, the engine warmed up or not, the air±fuel
ratio lean or rich, etc. at the time of the malfunction.
1 Are there any other codes (besides DTC P0116) being output?
YES Go to relevant DTC chart.
NO
DI6UZ±03
P21242 FI7210
A04485
Atmosphere
Flange
Platinum Electrode
Solid Electrolyte
(Zirconia Element)
Platinum Electrode
Heater
Coating (Ceramic)
Exhaust Gas CoverIdeal Air±Fuel Mixture
Output Voltage
Richer ± Air Fuel Ratio ± Leaner
DI±44
± DIAGNOSTICSENGINE
2001 PRIUS (RM778U)
DTC P0125 Insufficient Temp. for Closed Loop
Fuel Control
CIRCUIT DESCRIPTION
To obtain a high purification rate for the CO, HC and NOx components of the exhaust gas, a three±way
catalytic converter is used, but for the most efficient use of the three±way catalytic converter, the air±fuel
ratio must be precisely controlled so that it is always close to the stoichiometric air±fuel ratio.
The oxygen sensor has the characteristic whereby its output voltage changes suddenly in the vicinity of the
stoichiometric air±fuel ratio. This is used to detect the oxygen concentration in the exhaust gas and provide
feedback to the computer for control of the air±fuel ratio.
When the air±fuel ratio becomes LEAN, the oxygen concentration in the exhaust increases and the oxygen
sensor informs the ECM of the LEAN condition (small electromotive force: < 0.45 V).
When the air±fuel ratio is RICHER than the stoichiometric air±fuel ratio the oxygen concentration in the ex-
haust gas in reduced and the oxygen sensor informs the ECM of the RICH condition (large electromotive
force: > 0.45V).
The ECM judges by the electromotive force from the oxygen sensor whether the air±fuel ratio is RICH or
LEAN and controls the injection time accordingly. However, if malfunction of the oxygen sensor causes out-
put of abnormal electromotive force, the ECM is unable to perform accurate air±fuel ratio control.
The oxygen sensors include a heater which heats the zirconia element. The heater is controlled by the ECM.
When the intake air volume is low (the temp. of the exhaust gas is low) current flows to the heater to heat
the sensor for accurate oxygen concentration detection.
DTC No.DTC Detecting ConditionTrouble Area
P0125
After the engine is warmed up, oxygen sensor (bank 1 sensor
1) output does not indicate RICH ( 0.45 V) even once when
conditions (a), (b), and (c) continue for at least 50 sec.
(a) Engine speed: 800 rpm or more
(b) Vehicle speed: 40 ± 100 km/h (25 ± 62 mph)
(c) 20 sec. or more after starting engine
Fuel system
Air induction system
Injector
Ignition system
Gas leakage on exhaust system
Open or short in heated oxygen sensor (bank 1 sensor 1)
circuit
Heated oxygen sensor (bank 1 sensor 1)
ECM
DI6V2±03