2001 TOYOTA PRIUS AUX

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)

Battery ECU
TROUBLE CODE
BATTERY SOC
WOUT
WIN
DELTA SOC
IB MAIN BATTERY
BATT TEMP 1
BATT TEMP 2
BATT TEMP 3
BATT TEMP 4
BATT INSIDE AIR
NORMAL STATUS
PRE ONBOARD CH
ONBOARD CHARGE
OFF AVE CHG ST
COOLING FAN LO
COOLING FAN MID
COOLING FAN HI
SBL FAN ST RQST
AUX. BATT V
EQTR CHARGE ST
EQCO DF RERAY
CCTL
BATT BLOCK V1
BATT BLOCK V2
BATT BLOCK V3
BATT BLOCK V4
BATT BLOCK V5
BATT BLOCK V6
BATT BLOCK V7
BATT BLOCK V8
BATT BLOCK V9
BATT BLOCK V10
BATT BLOCK V11
BATT BLOCK V12
BATT BLOCK V13
BATT BLOCK V14
BATT BLOCK V15
BATT BLOCK V16
BATT BLOCK V17
BATT BLOCK V18
BATT BLOCK V19%
KW
KW
%
A
°F ( °C)
YES / NO
YES / NO
YES / NO
YES / NO
ON / OFF
ON / OFF
ON / OFF
ON / OFF
ON / OFF
ON / OFF
ON / OFFV
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V °F ( °C)
°F ( °C)
°F ( °C)
°F ( °C)
± DIAGNOSTICSHYBRID VEHICLE CONTROL SYSTEM
DI±185
2001 PRIUS (RM778U)

± DIAGNOSTICSHYBRID VEHICLE CONTROL SYSTEM
DI±193
2001 PRIUS (RM778U)
5. CHECK FOR INTERMITTENT PROBLEMS
(a) Perform a simulation test (See page IN±41).
In the simulation test, reproduce the driving condition at the trouble occurrence according to the cus-
tomer 's comments and freeze frame data recorded with DTC, such as an opening angle of the acceler-
ator pedal, SOC, engine coolant temperature, engine rpm, and MG/1MG2 rpm and torque.
(b) Check the connector and terminal (See page IN±41).
(c) Handle the connector (See page IN±41).
6. TOYOTA HAND±HELD TESTER DISPLAY ITEMS
TOYOTA Hand±held tester displayMeasurement Item
1 BEF LATST ORNumber of operation of 1 trip before last
1 BEF LATST TRPNumber of trips before last
2 BEF LATST ORNumber of operation 2 trips before last
2 BEF LATST TRPNumber of trips 2 before last
ABNML CON BR±HVCommunication malfunction between HV ECU and brake
ACC SENSOR MAINMain accelerator sensor
ACC SENSOR SUBSub accelerator sensor
ACC TENT TRBLETentative trouble of accelerator
ACC THROTTLEAccelerator throttle
ACCEL MODEHistory of acceleration and reduction
AIR CON REQUESTAir conditioner request
AUX. BATT LOWAuxiliary battery becomes week
AUX. BATT VVoltage of auxiliary battery
BATT HIGH TEMPTemperature of the battery is too high
BATT HIGH VOLTVoltage of the battery is too high
BATT LOW BOLTVoltage of the battery is low
BATT OVER LOADBattery is overloaded
BATT SAVE RQSTRequest to save the main battery
BATTERY FULLBattery full
BRAKE TORQBrake torque
CELL TEMP±MAXHighest temperature of all battery cells
CELL TEMP±MINLowest temperature of all battery cells
CHG RESTRICTIONCharge restriction
COOLANT TEMPWater temperature
CRUISE CONTROLCondition of the cruise control
DC/DC CONV STOPDC/DC converter stop signal
DC/DC CONV STOPFactors causing DC/DC converter to stop
DC/DC STOP FACTDC/DC converter has stopped at least once
DC/DC V UNSETDC/DC voltage is unsettled
DCHG RQST SOCDischarge request to adjust SOC
DISCHAG INHIBITBattery is inhibited to discharge

A14140
C4
ConverterHybrid Vehicle
Control ECU
NODD
4L ± O
NODD 4
H12 DI±266
± DIAGNOSTICSHYBRID VEHICLE CONTROL SYSTEM
2001 PRIUS (RM778U)
DTC P3125 Converter & Inverter Assembly Malfunction
CIRCUIT DESCRIPTION
If driving the vehicle with the DCDC converter malfunctioning, the voltage of the auxiliary battery will drop,
which will make it impossible to keep driving the vehicle. Therefore, HV ECU checks the operation of the
DCDC converter and gives warning to the driver if malfunction is detected.
HINT:

When using an OBD scan tool other than TOYOTA hand±held tester, check all the steps.

When using TOYOTA hand±held tester, confirm the information code and check it.
DTC P3125 ± Information code 263, 264, 265
INF. Code.Detecting ConditionTrouble Area
263+B short in DCDC converter NODD wiring
264DCDC converter malfunction
Converter & inverter assembly

Wire harness265Open or GND short in DCDC converter NODD wiring
Wire harness
WIRING DIAGRAM
DI838±02

F12396
DLC3
TOYOTA hand±held tester
A04550
DLC3
912 3 4 56 78
16 15 14 13 12 11 10
DI±316
± DIAGNOSTICSHV BATTERY CONTROL SYSTEM
2001 PRIUS (RM778U)

To check the Diagnostic Trouble Codes (DTC), con-
nect the TOYOTA hand±held tester to the Data Link
Connector 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.

Freeze frame data:
Freeze frame data records the battery condition
when a malfunction is detected.
When troubleshooting, this is useful for knowing the
battery condition.
(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

A14089
B12009
F12396
DLC3
TOYOTA hand±held tester
± DIAGNOSTICSHV BATTERY CONTROL SYSTEM
DI±317
2001 PRIUS (RM778U)
(2) Inspect the auxiliary battery, fuses, fusible links, wir-
ing harness, connectors and ground.
(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 or abnormality in the system.
(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 and freeze frame data and note them down.
(For operating instructions, see the TOYOTA hand±
held tester operator's manual).
Since the HV battery ECU stores DTC and freeze
frame data, when troubleshooting, check all of the
DTC, write down the freeze fame data and perform
inspection according to the procedures of ºCircuit
Inspectionº.
Because the HV battery ECU is communicating with
the HV ECU, if any DTC is stored in the HV battery
ECU, check and record DTC stored in the HV ECU
(For tables for DTC, see page DI±177).
(5) See a related page to confirm details of the DTC.

F12396
DLC3
TOYOTA hand±held tester
DI±318
± DIAGNOSTICSHV BATTERY CONTROL SYSTEM
2001 PRIUS (RM778U)
(d) Clear DTC after completion of repair.
(1) Connect the TOYOTA hand±held tester to the
DLC3.
HINT:
Before clearing, check that DTC for the HV battery ECU, DTC
for the ECU which is related with freeze frame data and the
freeze frame data are recorded.
(2) Operate the TOYOTA hand±held tester to erase the
DTC (See the TOYOTA hand±held tester opera-
tor 's manual.).
4. CHECK FOR INTERMITTENT PROBLEMS
(a) Perform a simulation test (See page IN±30).
HINT:
In the simulation test, reproduce the condition at trouble occurrence based on the customer's comments and
the freeze frame data recorded with the DTC.
(b) Check the connector and terminal (See page IN±41).
(c) Handle the connector (See page IN±41).
5. TOYOTA HAND±HELD TESTER DISPLAY ITEMS
TOYOTA hand±held tester displayMeasurement Item
BATTERY SOCBattery State of charge
ONB CHARGE TIMECumulative number of times of on±board equalizing charging
BATTERY LO TIMECumulative number of times of battery dies
DC INHIBIT TIMECumulative number of times of discharge inhibition
IB MAIN BATTERYIB main battery current (with correction)
BATT BLOCK V#Battery block voltage
BAT BLOCK MIN VBattery block minimum voltage
MIN BAT BLOCK #Minimum voltage battery block
BAT BLOCK MAX VBattery block maximum voltage
MAX BAT BLOCK #Maximum voltage battery block
BATT INSIDE AIRAmbient temperature inside battery pack
BATTERY TOO HI #Cumulative number of times of too±high battery voltage
VMF FAN VOLTAGEBattery cooling fan voltage
AUX. BATT VAuxiliary battery voltage
WINCharge restriction value
WOUTDischarge restriction value
DELTA SOCDifference between MAX. and MIN. values of SOC at every battery block.
SBLW FAN ST RQSSBL cooling fan stop request signal
COOLING FAN HICooling fan operation in high speed
COOLING FAN MIDCooling fan operation in middle speed
COOLING FAN LOCooling fan operation in low
CCTLOff±board equalizing charge control signal
EQC0 DF RELAYEQC0 dead front relay
EQTR CHARGE STEQTR uniform charging start signal
ONBORD CHARGEOn±board equalizing charging status
PRE ONBORDE CHPre±On±board charging status
NORMAL STATUSNormal status
INSIDE RESIST #Inside resistance

± DIAGNOSTICSHV BATTERY CONTROL SYSTEM
DI±333
2001 PRIUS (RM778U)
3 Is DTC P3009 of battery ECU being output?
PREPARATION:
(a) Before clearing the DTC, check that related DTC and freeze frame data are recorded in the given table.
(b) With the shift lever in P, delete this DTC using a TOYOTA hand±held tester.
(c) Turn the ignition switch OFF and then ON (Do not turn to ST.), leave it alone for 1 min. and then check
for DTC.
CHECK:
Check that DTC P3009 is detected.
YES Go to step 8.
NO
4 Is DTC P3009 of battery ECU being output?
(Check for battery carrier catch bracket.)
PREPARATION:
(a) Under step 2 condition, turn the ignition switch OFF and disconnect the negative terminal of the auxilia-
ry battery.
(b) Remove the service plug.
(c) Using the service plug, turn the interlock counterclockwise to unlock.
(d) Remove the 3 nuts and battery carrier catch bracket.
(e) Connect the negative terminal of the auxiliary battery and turn the ignition switch ON to clear DTC.
HINT:
When the ignition switch is turned ON, DTC P3140 is stored in the HV ECU. This happens because the ser-
vice plug is removed, so continue the operation.
(f) After turning the ignition switch OFF, connect the service plug.
(g) Turn the ignition switch ON (to ST), leave it alone for 1 min. and then check for DTC.
CHECK:
Check that DTC P3009 is detected.
NO Check for contact between battery carrier catch
bracket and power cable and if any defect is
identified, replace defective part.
HINT:
If no defect is identified at inspection, entry of foreign matter or
water into the battery assembly or converter & inverter assem-
bly may be possible as a cause.
YES