O2 sensor TOYOTA PRIUS 2001 Service Repair Manual

± DIAGNOSTICSHYBRID VEHICLE CONTROL SYSTEM
DI±265
2001 PRIUS (RM778U)
INSPECTION PROCEDURE
1 Check for open, short and +B short in wire harness between HV transaxle gener-
ator temperature sensor GMT and GMTG terminals and HV ECU GMT and GMTG
terminals (See page IN±41).
HINT:
Confirm that there is no open circuit in the wire harness. If the voltage of the HV ECU GMT terminal is always
more than 5V with the ignition ON, the generator temperature sensor circuit has +B short.
NG Repair or replace wire harness.
OK
Check for open in generator temperature sensor and then replace HV transaxle generator.
Check generator temperature sensor (See page HV±40).
CIRCUIT DESCRIPTION
DTC P3120 ± Information code 258, 260
INF. Code.Detecting ConditionTrouble Area
258Generator temperature sensor malfunctionHV t l ( t )260Generator temperature sensor performance problem
HV transaxle (generator)
INSPECTION PROCEDURE
If the information code 258 or 260 is output, replace the HV transaxle generator.

A14121
InverterHybrid Vehicle
Control ECU
VBY 5
I10
6
I9 M±GINVB20
H11
26
H11VB
MIVG DI±268
± DIAGNOSTICSHYBRID VEHICLE CONTROL SYSTEM
2001 PRIUS (RM778U)
CIRCUIT DESCRIPTION
The HV ECU checks the inverter voltage and detects malfunction.
DTC P3125 ± Information code 266, 267, 268, 269, 270
INF. Code.Detecting ConditionTrouble Area
266Open or GND short in inverter voltage signal circuit
267+B short in inverter voltage signal circuit
268Inverter voltage signal is inconsistent with battery voltage
Converter & inverter assembly269Inverter voltage sensor malfunction
Converter & inverter assembly

Wire harness
270
Abnormality of line connection of inverter voltage signal
circuit (when there is a history that the state of malfunction
continued during inverter fail safe mode)

Wire harness
WIRING DIAGRAM

A14121
InverterHybrid Vehicle Control ECU
M±SINVG 7
I10
6
I9 M±GINVB21
MSIV
MIVG 26
H11H11
± DIAGNOSTICSHYBRID VEHICLE CONTROL SYSTEM
DI±273
2001 PRIUS (RM778U)
CIRCUIT DESCRIPTION
The HV ECU checks the inverter temperature and controls the load limitation in order to prevent the inverter
from overheating. Also, it detects the abnormality of the line connection of the inverter temperature sensor
and the malfunction of the sensor itself.
DTC P3125 ± Information code 274, 275, 276, 277
INF. Code.Detecting ConditionTrouble Area
274Open or +B short in motor inverter temperature sensor
275GND short in motor inverter temperature sensor
Converter & inverter assembly
276Motor inverter temperature sensor malfunction

Converter & inverter assembly

Wire harness
277Motor inverter temperature sensor performance problem
WIRING DIAGRAM

DI±274
± DIAGNOSTICSHYBRID VEHICLE CONTROL SYSTEM
2001 PRIUS (RM778U)
INSPECTION PROCEDURE
1 Check for open, short and +B short in wire harness between HV ECU MIT and
MIVG terminals and converter & inverter M±INVT, M±GINV terminals (See page
IN±41).
HINT:
Confirm that there is no open circuit in the wire harness. If the voltage between the HV ECU MIT or MIVG
terminal and body ground is always more than 5V with the ignition ON, the motor inverter temperature sensor
circuit has +B short.
NG Repair or replace wire harness.
OK
Check for open in motor inverter temperature sensor and then replace converter & inverter as-
sembly. Check motor inverter temperature sensor (See page HV±14).

A14123
InverterHybrid Vehicle Control ECU
M±GINVB
2
I10 M±IWAR B
W
G 4
I103
I101
I106
I9
M±IWB M±IVB M±IVAMIVG
MIWAMIWB MIVB MIVA 26
16
7
17
25
H11 H11 H11 H11 H11
± DIAGNOSTICSHYBRID VEHICLE CONTROL SYSTEM
DI±279
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 288, 289, 290, 292, 294, 296, 297, 298, 300, 302,
INF. Code.Detecting ConditionTrouble Area
289Open in motor inverter current sensor (V phase sub sensor)
292Open in motor inverter current sensor (V phase main sen-
sor)
297Open in motor inverter current sensor (W phase sub sen-
sor)
300Open in motor inverter current sensor (W phase main sen-
sor)
288Motor inverter current sensor malfunction (V phase sub
sensor)
Ct&it bl
290Motor inverter current sensor malfunction (V phase main
sensor)
Converter & inverter assembly

Wire harness
294Motor inverter current sensor V phase performance prob-
lem
296Motor inverter current sensor malfunction (W phase sub
sensor)
298Motor inverter current sensor malfunction (W phase main
sensor)
302Motor inverter current sensor W phase performance prob-
lem
WIRING DIAGRAM

A14123
InverterHybrid Vehicle Control ECU
M±GINVB
2
I10 M±IWAR B
W
G 4
I103
I101
I106
I9
M±IWB M±IVB M±IVAMIVG
MIWAMIWB MIVB MIVA 26
16
7
17
25
H11 H11 H11 H11 H11
± DIAGNOSTICSHYBRID VEHICLE CONTROL SYSTEM
DI±281
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 291, 293, 295, 299, 301, 303
INF. Code.Detecting ConditionTrouble Area
291
293
295When there is a history that the state of malfunction contin-
Converter & inverter assembly
299
When there is a history that the state of malfunction contin
ued during inverter fail safe mode.

Converter & inverter assembly

Wire harness
301
g
303
WIRING DIAGRAM

± 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