2001 TOYOTA PRIUS brake light

DI82L±02
± DIAGNOSTICSHYBRID VEHICLE CONTROL SYSTEM
DI±197
2001 PRIUS (RM778U)
DIAGNOSTIC TROUBLE CODE CHART
HINT:
Parameters listed in the chart may not be exactly the same as your reading due to the type of instrument
or other factors.
If a malfunction code is displayed during the DTC check in the check mode, check the circuit for that code
listed in the table below. For the details of each code, turn to the page referred to under the ''See page'' for
the respective ''DTC No.'' in the DTC chart.
DTC No.
(See page)Detection ItemTrouble Area
Hybrid
System
Warning
Light*
Memory
B2799
(DI±210)Immobilizer Malfunction
Wire Harness

Immobilizer System
C2692
(DI±212)Regenerative Brake Check±
C2693
(DI±212)Regenerative Brake Check±X
P1120
(DI±213)Accelerator Pedal Position
Sensor Circuit Malfunction
Accelerator Pedal Position Sensor

Wire Harness
P1520
(DI±215)Stop Light Switch (Cruise Con-
trol System) Malfunction
Stop Light Switch

Wire Harness

Brake ECU
X
P1566
(DI±217)Cruise Control System Malfunc-
tion
Stop Light Switch

Brake ECU

Wire Harness
X
P1600
(DI±219)BATT Malfunction
HV Fuse

Wire Harness
P1780
(DI±221)Park/Neutral Position Switch
System Malfunction
Park/Neutral Position Switch

Wire Harness
P3000
(DI±223)HV Battery Malfunction

HV Battery System

High Voltage Fuse

Power Cable

HV Battery Cooling System
/X
P3001
(DI±224)HV Battery ECU Malfunction
Battery ECU
P3004
(DI±225)Power Cable Malfunction

Power Cable

HV Battery System

Service Plug

System Main Relay

Converter & Inverter Assembly
/X
P3100
(DI±229)HV ECU Malfunction

Wire Harness

HV ECU

ECM

Crankshaft Position Sensor

Camshaft Position Sensor

Ignition Switch

P3101
(DI±237)Engine System Malfunction
Engine

HV Transaxle
P3105
(DI±238)Battery ECU Communication Cir-
cuit Malfunction
Wire Harness

Battery ECU
P3106
(DI±240)ECM Communication Circuit
Malfunction
Wire Harness

ECM/X

DI±198
± DIAGNOSTICSHYBRID VEHICLE CONTROL SYSTEM
2001 PRIUS (RM778U)P3107
(DI±242)
Airbag ECU Communication Cir-
cuit Malfunction
Wire Harness

Airbag Sensor Assembly
P3108
(DI±244)A/C Amplifier Communication
Circuit Malfunction
Wire Harness

A/C AmplifierX
P3109
(DI±245)Brake ECU Communication Cir-
cuit Malfunction
Wire Harness

Brake ECU
P3110
(DI±247)IGCT Relay Malfunction
Wire Harness

IGCT Relay
P3115
(DI±249)System Main Relay Malfunction

Wire Harness

System Main Relay

HV ECU

P3120
(DI±252)HV Transaxle Malfunction

HV Transaxle

Wire Harness

System Main Relay

P3125
(DI±266)Converter & Inverter Assembly
Malfunction
Converter & Inverter Assembly

Wire Harness
P3130
(DI±302)Inverter Cooling System Mal-
function

Inverter Water Pump

Wire Harness

IG2 Relay

Electric Cooling Fan System

P3135
(DI±305)Circuit Breaker Sensor Malfunc-
tion
Circuit Breaker Sensor

Wire Harness
P3140
(DI±307)Interlock Malfunction

Interlock Switch

Inverter Terminal Cover

Converter & Inverter Assembly

Wire Harness

P3145
(DI±310)Vehicle Speed Sensor Circuit
Malfunction
Wire HarnessX
*: : Hybrid system warning light lights up. X: Hybrid system warning light does not light up.

± DIAGNOSTICSHYBRID VEHICLE CONTROL SYSTEM
DI±199
2001 PRIUS (RM778U)
INFORMATION CODE (TOYOTA Hand±held tester only)
DTC NO.INF. CodeDetection ItemDetecting Condition
B2799101Immobilizer MalfunctionNo input of signal from transponder key ECU
C2692102Regenerative Brake CheckRegenerative brake check
C2693103Regenerative Brake CheckRegenerative brake check
104Open or short in main accelerator sensor circuit
105+B short in main accelerator sensor circuit
106Main sensor internal error
107Open or short in sub accelerator sensor circuit
108+B short in sub accelerator sensor circuit
P1120109Accelerator Pedal Position
Sensor Circuit MalfunctionSub sensor internal errorP1120
11 0Sensor Circuit MalfunctionWhen difference between main sensor value and sub sensor value is large
111When sub sensor value changes while main sensor value does not
11 2When main sensor value changes while sub sensor value does not
11 3When any of the information code 104 ± 112 continues to appear
11 4Accelerator pedal not smoothly returning to original position
P152011 5
Stop Light Switch
(Cruise Control System)
Malfunction
Open or short in stop light switch circuit
P156611 6Cruise Control System
MalfunctionWhen STP signal of HV ECU is inconsistent with that of brake ECU, with
cruise control indicator ON
P160011 7BATT MalfunctionHV ECU back±up power source circuit malfunction
11 8When more than 2 main signals are ON
11 9P k/N t l P iti S it hWhen main signal is not turned ON even though sub signal has been input
P1780120Park/Neutral Position Switch
System MalfunctionOpen or short in sub sensor circuit
121
System Malfunction
When shift position detected by main signal is different from that detected
by sub signal
123HV B tt M lf tiInput of abnormal signal from battery ECU (HV battery system malfunction)
125HV Battery MalfunctionInput of abnormal signal from battery ECU (high voltage fuse blown out)
P3000388Discharge Inhibition Control
MalfunctionWhen charged battery is low due to leaving the vehicle in N position, gas
shortage or HV system malfunction
389Drop of High VoltageWhen main battery is dead or main battery is dead due to HV system mal-
function
P3001129HV Battery ECU MalfunctionBattery ECU malfunction
130HV Battery MalfunctionWhen HV battery voltage becomes lower than inverter voltage
P3004
131
PCblMlfti
When main fuse is blown out, service plug is disconnected or limiter resis-
tance is cut off
P3004
132
Power Cable MalfunctionWhen inverter voltage sensor is malfunctioning or limiter resistance value
increases
133HV Battery MalfunctionInput of abnormal signal from battery ECU
134HV ECU I t l EHV ECU Internal Error
135HV ECU Internal ErrorHV ECU Internal Error
P3100136GO Signal ErrorOpen or short in GO signal circuit
137Engine Speed Sensor
MalfunctionEngine speed sensor malfunction

DI82N±02
A02508A04997
HV ECU Terminals
H12 H13 H14H11H10
1 2 4 5 6 7 8 93
10 11 12 13 14 1615 19 20 1718 21
22 23 24 25 26 27 28 29 30 311 2 4 5 63 7
8 9 10 11 12 13 14 16 15
19 20 1718 21 22 23 241 2 4 5 63
7 8 9 10 11 12
14 13 15 16 171 2 3 4 65 7 8 9
10 11 12 13 14 16 15 19 1718
20 21 22 25 26 27 28 23241 2 3 4 5 6 7
8 9 10 11 12 13 14 15
17 18 16 19 20 21 22
± DIAGNOSTICSHYBRID VEHICLE CONTROL SYSTEM
DI±207
2001 PRIUS (RM778U)
TERMINALS OF ECU
Symbols (Terminals No.)Wiring ColorConditionSTD Voltage (V)
BATT (H14±3) e GND1
(H14±31)G±Y eW±BAlways9 ± 14
+B1 (H14±4) e GND1
(H14±31)W±G e W±BIgnition switch ON and ºREADYº light ON9 ± 14
+B2 (H14±5) e GND1
(H14±31)W±G e W±BIgnition switch ON and ºREADYº light ON9 ± 14
IGSW (H13±7) e GND1
(H14±31)B±W e W±BIgnition switch ON9 ± 14
ST2 (H13±6) e GND1
(H14±31)R±W e W±BIgnition switch ST9 ± 14
ST1 (H14±2) e GND1BYWBBrake pedal is depressedBelow 0.5ST1 (H14 2) e GND1
(H14±31)B±Y e W±BBrake pedal is released9 ± 14
STP (H14±1) e GND1GWWBBrake pedal is depressed9 ± 14STP (H14 1) e GND1
(H14±31)G±W e W±BBrake pedal is releasedBelow 0.5
VCP1 (H14±13) e GND1
(H14±31)Y e W±BIgnition switch ONApprox. 5
VPA1 (H14±14) e GND1GWBIgnition switch ON and accelerator pedal is releasedApprox. 1VPA1 (H14 14) e GND1
(H14±31)G eW±BIgnition switch ON and accelerator pedal is fully depressedApprox. 4
EP1 (H14±12) e GND1
(H14±31)L e W±BIgnition switch ONBelow 0.5
VCP2 (H14±23) e GND1
(H14±31)B e W±BIgnition switch ONApprox. 5
VPA2 (H14±15) e GND1WWBIgnition switch ON and accelerator pedal is releasedApprox. 1VPA2 (H14 15) e GND1
(H14±31)W eW±BIgnition switch ON and accelerator pedal is fully depressedApprox. 4
EP2 (H14±22) e GND1
(H14±31)R e W±BIgnition switch ONBelow 0.5
P (H13 15)GND1 (H14 31)LRWBShift lever is P positionBelow 1P (H13±15) e GND1 (H14±31)L±R eW±BExcept shift lever is P position4 or more
R (H13 14)GND1 (H14 31)RBWBShift lever is R positionBelow 1R (H13±14) e GND1 (H14±31)R±B eW±BExcept shift lever is R position4 or more
N (H13 13)GND1 (H14 31)LWWBShift lever is N positionBelow 1N (H13±13) e GND1 (H14±31)L±W eW±BExcept shift lever is N position4 or more
D (H13 23)GND1 (H14 31)LBWBShift lever is D positionBelow 1D (H13±23) e GND1 (H14±31)L±B eW±BExcept shift lever is D position4 or more
B (H13 22)GND1 (H14 31)LG RWBShift lever is B positionBelow 1B (H13±22) e GND1 (H14±31)LG±R eW±BExcept shift lever is B position4 or more

A14147
H14Hybrid Vehicle
Control ECU
H14
BatteryMAIN
B±G1 1
F1811 1
111
F13 2
3
2
2 Engine Room J/BSTP
ST1± G±W
J15 E
2 J14D J/C
G±W S3
Stop Light
SW
R±B
R±B4B±Y B±W B±W B
B
J24 J25 ID1J/C
B±W
I15
Ignition SW
W±RW±R
67
9
IG2AM2
Instrument Panel J/B
STOP 2C
2K2H 2G9
1J 1BAM2
B
W
F12 F11
DC/DC
Fusible Link Block No. 1 Fusible Link
Block No. 16
± DIAGNOSTICSHYBRID VEHICLE CONTROL SYSTEM
DI±215
2001 PRIUS (RM778U)
DTC P1520 Stop Light Switch (Cruise Control System)
Malfunction
CIRCUIT DESCRIPTION
The HV ECU detects the malfunction of the cruise control system and inhibits the operation of the cruise
control.
It detects faulty output of the STP and ST1± signals sent from the stop light switch or an error signal from
the brake ECU.
DTC P1520 ± Information code 115
INF. code.Detecting ConditionTrouble Area
11 5Open or short in stop light switch circuit

Stop light switch

Wire harness

Brake ECU
WIRING DIAGRAM
DI82R±02

DI±216
± DIAGNOSTICSHYBRID VEHICLE CONTROL SYSTEM
2001 PRIUS (RM778U)
INSPECTION PROCEDURE
1 Is DTC of brake ECU being output?
YES Check DTC of brake ECU (See page DI±358).
NO
2 Check voltage between terminal 2, 3 of stop light switch and body ground.
NG Repair or replace wire harness or connector.
OK
3 Check for open and short in wire harness between stop light switch and termi-
nals STP, ST1± of HV ECU (See page IN±41).
NG Repair or replace wire harness.
OK
Check and replace stop light switch (See page BE±32).

± DIAGNOSTICSHYBRID VEHICLE CONTROL SYSTEM
DI±217
2001 PRIUS (RM778U)
DTC P1566 Cruise Control System Malfunction
CIRCUIT DESCRIPTION
The HV ECU and the brake ECU monitor the same STP signal. If any difference is identified between both
received signals, the HV ECU outputs an error.
DTC P1566 ± Information code 116
INF. code.Detecting ConditionTrouble Area
11 6When STP signal of HV ECU is inconsistent with that of brake
ECU, with cruise control indicator ON.
Brake ECU

Wire harness

Stop light switch
WIRING DIAGRAM
Refer to DI±215.
INSPECTION PROCEDURE
1 Is DTC of brake ECU being output (See page DI±351)?
YES Check DTC of brake ECU (See page DI±351).
NO
2 Check for +B short in wire harness between stop light switch and terminals STP,
ST1±of HV ECU (See page IN±41).
HINT:
Under the normal condition, the voltage of the HV ECU STP terminal is 0V when the brake pedal is released
with the ignition OFF. If there is any output of voltage at this time, the stop light switch circuit has +B short.
NG Repair or replace wire harness.
OK
DI82S±02

DI±218
± DIAGNOSTICSHYBRID VEHICLE CONTROL SYSTEM
2001 PRIUS (RM778U)
3 Check for open and short in wire harness between stop light switch and brake
ECU.
NG Repair or replace wire harness.
OK
Check and replace stop light switch (See page BE±32).