TOYOTA PRIUS 2001 Service Repair Manual

A14008
START
(±)
(+)ACT
± DIAGNOSTICSENGINE
DI±173
2001 PRIUS (RM778U)
OBDII scan tool (excluding TOYOTA hand±held tester):
1 Check voltage between terminal ACT of ECM and body ground.
PREPARATION:
Start the engine.
CHECK:
Measure voltage between terminal ACT of ECM connector and
body ground when A/C switch is turned to ON and OFF.
OK:
A/C switch conditionVoltage
ON9 ± 14 V
OFFBelow 1.5 V
OK Check and repair ECM. (See page IN±41)
NG
2 Check for open and short in harness and connector between ECM and A/C am-
plifier. (See page IN±41)
NG Repair or replace harness or connector.
OK
Check and replace A/C amplifier.

DI82J±02
Prius Problem Check Sheet
Vehicle
Specifications
Please fill in the blanks within bold frame.Name of DealerPerson in Charge at
HeadquartersPerson in Charge
at Dealer
Model CodeOffice
Vehicle Delivery Date
Frame No.
Unit No. etc.
Option . . . :
( ) Navigation (equipped by ( ) MOP ( ) dealer) ( ) Cold climate specification
( ) others( )Problem Occurrence Date
Service Entry Date NHW11±
. .
. .Registration datemiles
. .
Contents of complaint (Status when and before/after occurring in
the order of events as correct as possible)Characteristics of Customer
Gender
Age
Occupation
Vehicle used before
Main use area
Frequency in use
Others times/day or
week or month
Status of engineOthers
Interview Results
( ) Male ( ) Female
suburbs ( ) %
Others ( ) ( ) %
city area ( ) %
mountain area ( ) %
Driving ConditionRoad Condition
Vehicle Condition
Vehicle Speed
km/h
( ) when starting
( ) when according
( ) When
normal driving
( ) when
decelerating
( ) when braking
( ) when shopping
( ) when parking
( ) when turning
( ) when
ABS actuating
( ) others
( )( ) flat road
( ) up hill ( ) down
hill incline of
° /%
distance
km
( ) dry paved road
( ) wet paved road
( ) rough paved road
( ) unpaved road
( ) snowy/frozen
road
( ) bump/curb
( ) others
( )( ) when starting
( ) right after
starting
( ) until min.
after starting
( ) until min.
after starting
of driving
( ) when shopping
system
( ) while shopping
engine
( ) when starting
engine
( ) when revolving
engineHV Battery
indication
( ) 4/4 ( ) 3/4
( ) 2/4 ( ) 1/4
( ) unidentified
Shift position
(indication)
( ) P ( ) R ( ) N
( ) D ( ) B
( ) when operating
"Weather:
A/C status
( ) no indication
( ) unidentified
( ) A/C ( ) FULL
( ) OFF
( ) unidentifiedWarning light
(MIL)
( ) ON ( ) OFF
( ) PS
( ) main battery
( ) HV!
( ) engine
( ) charge
( ) output
control
( ) brake
( ) ABS
( ) others
( )
Temperature:
°C
Brake operation
( ) brake slowly
( ) Brake suddenly
( ) use two pedals
system
Frequency in
occurrence
( ) always
( ) sometimes
( ) only once
Fuel level
( ) segmentsmphOdometer Reading
mph
°F km
± DIAGNOSTICSHYBRID VEHICLE CONTROL SYSTEM
DI±175
2001 PRIUS (RM778U)
CUSTOMER PROBLEM ANALYSIS CHECK

Verification Results of Warning Light
Engine
HV
INF. code
HV battery
Vehicle Verification Results
( ) ON ( ) OFF
( ) engine ( ) HV
( ) HV battery
( ) output control warning light
( ) brake ( ) ABS ( ) charge ( ) PS
( ) others
( )Verification Results of Diagnostic Code
Brake
PS
Vehicle Inspection Results (Verification items, reason to identify/presume the cause parts, etc.)
Replacement Parts
problem parts: No/Yes (Sending date: . . )Duplication Status
( ) always
( ) sometimes
( ) no reproduction
Confirmation Results
After Repair
( ) Normal
( ) reproduction
( ) others ( )
DI±176
± DIAGNOSTICSHYBRID VEHICLE CONTROL SYSTEM
2001 PRIUS (RM778U)

B04757
DI82K±02
A14091
F12396
DLC3
TOYOTA Hand±held Tester
± DIAGNOSTICSHYBRID VEHICLE CONTROL SYSTEM
DI±177
2001 PRIUS (RM778U)
PRE±CHECK
1. PRECAUTION
(a) When distinguishing trouble and replace the defective
part, take necessary preventive measures against an
electric shock (See page IN±4).
(b) Some portions of the wiring harness in the THS vehicle
have circuits to which a high voltage is applied. To prevent
an electrical shock, be sure to observe the following:
(1) Wear insulated gloves during inspection.
(2) Remove a service plug and do not start any repair
operation before 5 minutes have passed. Then,
confirm that the voltage at the output terminals has
dropped down to 12 V or less.
(3) Use insulated tools during inspection.
(4) When disengaging the wiring connectors, hold the
connector bodies to avoid pulling the wires. When
engaging the wiring connectors, be sure to engage
them securely.
(c) Do not leave the tools or parts (bolts, nuts, etc.) inside the
cabin.
(d) Do not carry metallic objects such as mechanical pencils
or scales.
2. DIAGNOSIS SYSTEM
(a) Description

The HV control ECU has a self±diagnosis system
by which malfunction in the computer itself or in
THS components is detected and the Hybrid ve-
hicle warning light in the multi±information display
are lighted up.

To check the Diagnostic Trouble Codes (DTC), con-
nect the hand±held tester to the Data Link Connec-
tor 3 (DLC3) on the vehicle. The TOYOTA hand±
held tester also enables you to erase the DTC and
check freeze frame data and various forms of THS
data.

A04550
DLC3
912 3 4 56 78
16 15 14 13 12 11 10
DI±178
± DIAGNOSTICSHYBRID VEHICLE CONTROL SYSTEM
2001 PRIUS (RM778U)

Freeze frame data:
As the freeze frame data records the driving condi-
tion when a malfunction is detected, when trouble-
shooting, it is useful for determining whether the ve-
hicle was running, braked, stopped or reversed.
(b) Check the DLC3.
The HV control ECU conforms to ISO 14230 for commu-
nication.
The terminal arrangement of the DLC3 complies with
SAEJ1962 and matches the ISO 14230 format.
Terminal No.Connection/Voltage or ResistanceCondition
7Bus
Line/Pulse generationDuring transmission
4Chassis Ground e Body Ground/1 W or lessAlways
5Signal Ground e Body Ground/1 W or lessAlways
16Battery Positive e Body Ground/10 ± 15 VAlways
HINT:
If your display shows UNABLE TO CONNECT TO VEHICLE
when you have connected the cable of the TOYOTA hand±held
tester to the DLC3, turned the motor switch ON and operated
the tester, there is a problem in the vehicle or tool.

If communication is normal when the tool is connected to
another vehicle, inspect the DLC3 on the original vehicle.

If communication is still not possible when the tool is con-
nected to another vehicle, the problem is probably in the
tool itself, so consult the Service Department.
3. INSPECT DIAGNOSIS
(a) Check the auxiliary battery.
(1) Measure the voltage of the auxiliary battery.
Voltage: 10 ± 15 V
(2) Inspect the auxiliary battery, fuses, fusible links, wir-
ing harness, connectors and ground.

A14089
B12009
F12396
DLC3
TOYOTA Hand±held Tester
± DIAGNOSTICSHYBRID VEHICLE CONTROL SYSTEM
DI±179
2001 PRIUS (RM778U)
(b) Check the master warning light.
(1) Turn the ignition switch ON and confirm that the
master warning light comes on.
HINT:
If the master warning light does not come on, suspect a burnt
fuse, burnt bulb, or open in wiring harness.
(2) When the ºREADYº light is ON, the master warning
light should go off.
If the lamp remains on, the diagnosis system has detected a
malfunction in the system or the meassage such as ºWhen you
park your care, make sure you shift to Park P.º and ºThe batter-
ies will not charge if the shifter is Nº appears on the multi±in-
formation display.
Since DTC may be stored even though the lamp is OFF, be sure
to check DTC.
(c) Check the DTC.
(1) Prepare a TOYOTA hand±held tester.
(2) Connect the TOYOTA hand±held tester to the
DLC3.
(3) Turn the ignition switch ON and push the TOYOTA
hand±held tester main switch ON.
(4) Use the TOYOTA hand±held tester to check the
DTC, information code and freeze frame data and
note them down. (For operating instructions, see
the TOYOTA hand±held tester operator's manual).
HINT:

For one DTC, the HV diagnosis system can memorize
more than one information code and freeze frame data
corresponding to them. Therefore, when troubleshooting,
check all of the information codes, record the freeze
frame data and then start inspection according to the pro-
cedures of ºCircuit Inspectionº.

The HV ECU is communicating with each ECU of the en-
gine brake, HV battery and EMPS. So, if a warning is out-
put from the HV control system, check and record DTCs
of all ECUs. (See tables on the following pages.)
(5) See a related page to confirm details of the DTC.

HV ECU±DTC & Information #
INFORMATION 1
INFORMATION 2
INFORMATION 3
INFORMATION 4
INFORMATION 5
INFORMATION 1
INFORMATION 2
INFORMATION 3
INFORMATION 4
INFORMATION 5
INFORMATION 1
INFORMATION 2
INFORMATION 3
INFORMATION 4
INFORMATION 5
INFORMATION 1
INFORMATION 2
INFORMATION 3
INFORMATION 4
INFORMATION 5
HV ECU±Information & Freezed frame data
MG1 REV
MG2 REV
MG1 TORQ
MG2 TORQ
POWER RQST
ENGINE SPD
MCYL CTRL POWER
SOC
WOUT CTRL POWER
WIN CTRL POWER
DRIVE CONDITION
INVERT TEMP ± MG1
INVERT TEMP ± MG2
MG1 TEMP
MG2 TEMP
PWR RESOURCE VM
PWR RESOURCE IB
SHIFT SENSOR 1
ACC SENSOR MAIN
ENG STOP RQST
IDLING REQUEST
ENGINE FUEL CUTrpm
rpm
rpm N´m
NmW
W
W%
( °C)
V
V A
Yes / No
Yes / No
Yes / NoHV BATT CH RQST
HCAC ABSRT RQST
ENG WARM UP RQT
STOP SW COND
CRUISE CONTROL
AUX. BATT V
EXCLUSIVE INFO1
EXCLUSIVE INFO2
EXCLUSIVE INFO3
EXCLUSIVE INFO4
EXCLUSIVE INFO5
EXCLUSIVE INFO6
LOAD CONDITION
DRIVING PATTEN1
DRIVING PATTEN2
DRIVING PATTEN3
IG OFF IN DRVIN
SG B IN REDUCIN
SG N IN REDUC/P
STEP ACC&BRAKE
IG OFF TIME
OCCURRENCE ORDERV Yes / No
Yes / No
Yes / No
Yes / No
Yes / No
Yes / No
Yes / No
Yes / No
Yes / No MG1 / MG2
min
± DTC
DTC
DTC
DTC
N´m
INFORMATION
°F
( °C) °F
( °C) °F
( °C) °F DI±180
± DIAGNOSTICSHYBRID VEHICLE CONTROL SYSTEM
2001 PRIUS (RM778U)

HV ECU±Operation History Data
LATEST OPER
LATEST TRIP
1 BEF LATST OR
1 BEF LATST TRP
2 BEF LATST OR
2 BEF LATST TRP
LATEST OPER
LATEST TRIP
1 BEF LATST OR
1 BEF LATST TRP
2 BEF LATST OR
2 BEF LATST TRP
LATEST OPER
LATEST TRIP
1 BEF LATST OR
1 BEF LATST TRP
2 BEF LATST OR
2 BEF LATST TRP
LATEST OPER
LATEST TRIP
1 BEF LATST OR
1 BEF LATST TRP
2 BEF LATST OR
2 BEF LATST TRP
LATEST OPER
LATEST TRIP
1 BEF LATST OR
1 BEF LATST TRP
2 BEF LATST OR
2 BEF LATST TRP
LATEST OPER
LATEST TRIP
1 BEF LATST OR
1 BEF LATST TRP
2 BEF LATST OR
2 BEF LATST TRP SHIFT BEF READY
N RANGE CTRL 1
N RANGE CTRL 2
STEP ACCEL IN N
AUX. BATT LOW
HV INTERMITTENT
± DIAGNOSTICSHYBRID VEHICLE CONTROL SYSTEM
DI±181
2001 PRIUS (RM778U)

LATEST OPER
LATEST TRIP
1 BEF LATST OR
1 BEF LATST TRP
2 BEF LATST OR
2 BEF LATST TRP
LATEST OPER
LATEST TRIP
1 BEF LATST OR
1 BEF LATST TRP
2 BEF LATST OR
2 BEF LATST TRP
LATEST OPER
LATEST TRIP
1 BEF LATST OR
1 BEF LATST TRP
2 BEF LATST OR
2 BEF LATST TRP
LATEST OPER
LATEST TRIP
1 BEF LATST OR
1 BEF LATST TRP
2 BEF LATST OR
2 BEF LATST TRP
LATEST OPER
LATEST TRIP
1 BEF LATST OR
1 BEF LATST TRP
2 BEF LATST OR
2 BEF LATST TRP
LATEST OPER
LATEST TRIP
1 BEF LATST OR
1 BEF LATST TRP
2 BEF LATST OR
2 BEF LATST TRP
MG2 TEMP HIGH
MG1 TEMP HIGH
MG2 INV TEMP HIGH
MG1 INV TEMP HIGH
MAIN BATT LOW
RESIST OVR HEAT DI±182
± DIAGNOSTICSHYBRID VEHICLE CONTROL SYSTEM
2001 PRIUS (RM778U)

SHIFT POSITION
BRAKE TORQ
MG2 TORQ
MG1 TORQ
VEHICLE SPD
ACC THROTTLE
OCCURRENCE TRIP( km/h)
%
SHIFT POSITION
BRAKE TORQ
MG2 TORQ
MG1 TORQ
VEHICLE SPD
ACC THROTTLE
OCCURRENCE TRIP%
SHIFT POSITION
BRAKE TORQ
MG2 TORQ
MG1 TORQ
VEHICLE SPD
ACC THROTTLE
OCCURRENCE TRIP% ACCEL MODE 1
ACCEL MODE 2
ACCEL MODE 3
OVER VOLTAGE
OVER CURRENT
MG2 TEMP HIGH
MG1 TEMP HIGH
BATTERY FULL
CHG RESTRICTION
REGN BRK INFECTYes / No
Yes / No
Yes / No
Yes / No
Yes / No
Yes / No
Yes / No REGEN IH FACTOR
BATT LOW VOLT
DISCHAG INHIBIT
N RANG OVR TIME
BATT HIGH VOLT
BATT OVER LOAD
BATT HIGH TEMPYes / No
Yes / No
Yes / No
Yes / No
Yes / No
Yes / No
LOAT CONDITION
DRIVING PATTEN
DRIVING PATTEN
DRIVING PATTEN BATT SAVE RQST
DRIVING PATTERNN´m
N´m
N´m
N´m
N´m
N´m N´m
N´m
N´m
mph
( km/h) mph
( km/h) mph
± DIAGNOSTICSHYBRID VEHICLE CONTROL SYSTEM
DI±183
2001 PRIUS (RM778U)