2001 TOYOTA PRIUS O2 sensor

± DIAGNOSTICSHYBRID VEHICLE CONTROL SYSTEM
DI±283
2001 PRIUS (RM778U)
CIRCUIT DESCRIPTION
The HV ECU detects the malfunction of the motor inverter current sensor. It detects the malfunction of the
sensor system, not of the high voltage system.
DTC P3125 ± Information code 306, 307
INF. Code.Detecting ConditionTrouble Area
306Failure in monitoring motor torque performanceCt&it bl307Abnormal current value of motor
Converter & inverter assembly
INSPECTION PROCEDURE
If the information code 306 or 307 is output, check if other DTC or information codes are recorded. If they
are recorded, check and repair those codes first.
If the information code 306 or 307 alone is recorded, replace the converter & inverter assembly.
CIRCUIT DESCRIPTION
If the HV ECU detects the collision signal from the airbag or inverter, the HV ECU recognizes it as the destruc-
tion of the vehicle and then shuts down the high voltage system to ensure safety.
DTC P3125 ± Information code 308
INF. Code.Detecting ConditionTrouble Area
308Input of collision signal from airbag or inverter±
HINT:
When the vehicle collision occurs and the airbag is deployed, this information code will be recorded and the
high voltage system will be shut down.

A14121
InverterHybrid Vehicle Control ECU
M±INVTL 5
I11
6
I11 M±GINVB23
GIT
GIVG 27
H11H11
± DIAGNOSTICSHYBRID VEHICLE CONTROL SYSTEM
DI±289
2001 PRIUS (RM778U)
CIRCUIT DESCRIPTION
The HV ECU checks the generator temperature and controls the load limitation in order to prevent the gener-
ator from overheating. Also, it detects the abnormality of the line connection of the generator temperature
sensor and the malfunction of the sensor itself.
DTC P3125 ± Information code 312, 313, 314, 315
INF. Code.Detecting ConditionTrouble Area
312Open or +B short in generator inverter temperature sensor
313GND short in generator inverter temperature sensorCt&it bl314Generator inverter temperature sensor malfunction
Converter & inverter assembly

Wire harness
315Generator inverter temperature sensor performance prob-
lem

Wire harness
WIRING DIAGRAM

DI±290
± DIAGNOSTICSHYBRID VEHICLE CONTROL SYSTEM
2001 PRIUS (RM778U)
INSPECTION PROCEDURE
1 Check for open, short and +B short in wire harness between HV ECU GIT and
GIVG terminals and converter & inverter G±GINV or G±GINV terminals (See page
IN±41).
HINT:
Confirm that there is no open circuit in the wire harness. The generator inverter temperature sensor circuit
has +B short if the voltage between the HV ECU GIT or GIVG terminal and body ground is always more than
5V with the ignition ON.
NG Repair or replace wire harness.
OK
Check for open in generator inverter temperature sensor and then replace converter & inverter
assembly. Check generator inverter temperature sensor (See page HV±14).

A14123
InverterHybrid Vehicle
Control ECU
G±IVAB
5
I11
G±INVTL W
G
R 2
I124
I123
I121
I12
G±IWA G±IWB G±IVBGIVA
GITGIWA GIWB GIVB 19
8
18
28
23
H11H11 H11 H11 H11
± DIAGNOSTICSHYBRID VEHICLE CONTROL SYSTEM
DI±295
2001 PRIUS (RM778U)
CIRCUIT DESCRIPTION
The HV ECU detects the malfunction of the generator inverter current sensor. It detects the malfunction of
the sensor system, not of the high voltage system.
DTC P3125 ± Information code 326, 327, 328, 330, 332, 334, 335, 336, 338, 340
INF. Code.Detecting ConditionTrouble Area
327Open in generator inverter current sensor (V phase sub
sensor)
330Open in generator inverter current sensor (V phase main
sensor)
335Open in generator inverter current sensor (W phase sub
sensor)
338Open in generator inverter current sensor (W phase main
sensor)
326Generator inverter current sensor malfunction (V phase sub
sensor)

Converter & inverter assembly
328Generator inverter current sensor malfunction (V phase
main sensor)

Converter & inverter assembly

Wire harness
332Generator inverter current sensor V phase performance
problem
334Generator inverter current sensor malfunction (W phase
sub sensor)
336Generator inverter current sensor malfunction (W phase
main sensor)
340Generator inverter current sensor W phase performance
problem
WIRING DIAGRAM

A14123
InverterHybrid Vehicle
Control ECU
G±IVAB
5
I11
G±INVTL W
G
R 2
I124
I123
I121
I12
G±IWA G±IWB G±IVBGIVA
GITGIWA GIWB GIVB 19
8
18
28
23
H11H11 H11 H11 H11
± DIAGNOSTICSHYBRID VEHICLE CONTROL SYSTEM
DI±297
2001 PRIUS (RM778U)
CIRCUIT DESCRIPTION
The HV ECU detects the malfunction of the generator inverter current sensor. It detects the malfunction of
the sensor system, not of the high voltage system.
DTC P3125 ± Information code 329, 331, 333, 337, 339, 341
INF. Code.Detecting ConditionTrouble Area
329
331
333When there is a history that the state of malfunction contin-
Converter & inverter assembly
337
When there is a history that the state of malfunction contin
ued during inverter fail safe mode

Converter & inverter assembly

Wire harness
339
g
341
WIRING DIAGRAM

± DIAGNOSTICSHYBRID VEHICLE CONTROL SYSTEM
DI±299
2001 PRIUS (RM778U)
CIRCUIT DESCRIPTION
The HV ECU detects the malfunction of the generator inverter current sensor. It detects the malfunction of
the sensor system, not of the high voltage system.
DTC P3125 ± Information code 344, 345
INF. Code.Detecting ConditionTrouble Area
344Failure in monitoring generator torque performanceCt&it bl345Abnormal current value of generator
Converter & inverter assembly
INSPECTION PROCEDURE
If the information code 344 or 345 is output, check if other DTC or information codes are recorded. If they
are recorded, check and repair those codes first.
If the information code 344 or 345 alone is recorded, replace the converter & inverter assembly.

A14136
C3
Circuit
Breaker
Sensor1
2
H12AS1G Hybrid Vehicle
Control ECU
BR±B
G±RH1214
15
AS1
± DIAGNOSTICSHYBRID VEHICLE CONTROL SYSTEM
DI±305
2001 PRIUS (RM778U)
DTC P3135 Circuit Breaker Sensor Malfunction
CIRCUIT DESCRIPTION
The HV ECU checks the line connection of the circuit breaker sensor (collision signal) and gives warning
to the driver if malfunction is detected.
DTC P3135 ± Information code 348, 349
INF. code.Detecting ConditionTrouble Area
348GND short in circuit breaker sensor
Circuit breaker sensor
349Open or +B short in circuit breaker sensor

Circuit breaker sensor

Wire harness
WIRING DIAGRAM
DI83A±02

DI±306
± DIAGNOSTICSHYBRID VEHICLE CONTROL SYSTEM
2001 PRIUS (RM778U)
INSPECTION PROCEDURE
1 Check for open, short and +B short in wire harness between circuit breaker sen-
sor No. 1 and No. 2 terminals and HV ECU AS1G and AS1 terminals
(See page IN±41).
HINT:
Confirm that there is no open circuit in the wire harness. The circuit breaker sensor circuit has +B short if
the voltage of the HV ECU AS1 terminal is more than 5V with the ignition ON.
NG Repair or replace wire harness.
OK
Check for open in resistance between circuit breaker sensor terminals and then replace circuit
breaker sensor (Circuit breaker sensor resistance: 820 ± 82 W).