TOYOTA PRIUS 2001 Service Repair Manual

A14081
AM
A14082
Engine Room J/B
HV Fuse
DI±324
± DIAGNOSTICSHV BATTERY CONTROL SYSTEM
2001 PRIUS (RM778U)
INSPECTION PROCEDURE
HINT:
Read freeze frame data using a TOYOTA hand±held tester or OBD II scan tool. Because freeze frame data
records the battery condition when the malfunction is detected. When troubleshooting, this is useful for
knowing the battery condition.
1 Check voltage between terminal AM of Battery ECU connector and body ground.
PREPARATION:
Remove the luggage trim.
CHECK:
Measure the voltage between terminal AM of the Battery ECU
connector and body ground.
OK:
Voltage: 9 ± 14 V
OK Check and replace Battery ECU (See page
IN±41).
NG
2 Check HV fuse of engine room J/B.
PREPARATION:
Remove the HV fuse from the engine room J/B.
CHECK:
Check the continuity of the HV fuse.
OK:
Continuity
NG Check for short in all harness and components
connected to HV fuse.
OK
Check and repair harness or connector be-
tween battery and HV fuse, and HV fuse and
Battery ECU (See page IN±41).

A15624
HV ECUBattery ECU
HTD+
HTD±W
B 2
H13
20
H13W
B 1
IF2
2
IF26
B17
7
B17 DI±326
± DIAGNOSTICSHV BATTERY CONTROL SYSTEM
2001 PRIUS (RM778U)
DTC P3002 HV ECU Communication Malfunction
CIRCUIT DESCRIPTION
The battery ECU receives information of the AC ECU, system main relay connection signals, etc. sent from
the HV ECU, and stores DTC when an error is detected in the receives information.
DTC No.DTC Detecting ConditionTrouble Area
P3002No serial signals transmitted from HV ECU
Communication bus line

HV ECU
HINT:
Check DTC of other ECUs and see whether any communication error of the HV ECU is stored or not.
If HV communication errors are stored in then one ECU, replace the HV ECU.
WIRING DIAGRAM
DI826±01

± DIAGNOSTICSHV BATTERY CONTROL SYSTEM
DI±327
2001 PRIUS (RM778U)
INSPECTION PROCEDURE
1 Check for open and short in wire harness between HV ECU and battery ECU.
PREPARATION:
Disconnect the connector from the battery ECU and the HV ECU
CHECK:
Check that the communication bus line is not short or open.
Terminals for checking open and short:
HV ECU TerminalsBattery ECU Terminals
H13 ± 2B17 ± 6
H13 ± 20B17 ± 7
OK:
No open or short.
NG Repair or replace the wire harness.
OK
2 Stop operation of all optional electric products for vehicle and check if same
DTC is stored.
NO Stop using product that causes noise.
YES
Replace the HV ECU.

A13558
Power Cable
to System Main Relay,
InverterBattery ECU
Service Plug Assembly
High Voltage Fuse
Service Plug
Power CableBattery Block No. 10L±W
L
76
to System Main Relay,
Inverter
DI±328
± DIAGNOSTICSHV BATTERY CONTROL SYSTEM
2001 PRIUS (RM778U)
DTC P3005 High Voltage Fuse Snapped
CIRCUIT DESCRIPTION
A fuse is set in the service plug to protect high±voltage system parts.
DTC No.DTC Detecting ConditionTrouble Area
P3005Although interlock switch is connected, voltage of battery block
No. 10 is less than specified.
High voltage fuse

Power cable
WIRING DIAGRAM
DI827±01

± DIAGNOSTICSHV BATTERY CONTROL SYSTEM
DI±329
2001 PRIUS (RM778U)
INSPECTION PROCEDURE
1 Are there any other codes (besides DTC P3005) and other ECU being output?
YES Go to relevant DTC chart.
NO
2 Check continuity of high voltage fuse in the service plug assembly and check
condition of service plug terminal (Loosened, poor contact, etc.).
OK Repair or replace the power cable.
NG
Repair or replace the service plug or the high
voltage fuse in the service plug assembly.

DI±332
± DIAGNOSTICSHV BATTERY CONTROL SYSTEM
2001 PRIUS (RM778U) 4/27/01
DTC P3009 Leak Detected
CIRCUIT DESCRIPTION
Electric leak from the high±voltage system, which may seriously harm the human body, is detected by this
code.
DTC No.DTC Detecting ConditionTrouble Area
P3009Electric leak from high±voltage system
(Insulating resistance of power cable is 100 kW or less.)

Power cable

HV transaxle

Converter & inverter assembly

Battery cover

System main relay

Battery temperature sensor

Battery ECU

Battery carrier catch bracket

Main battery cable

Service plug assembly

HV battery assembly
INSPECTION PROCEDURE
1 Is DTC P3125 of HV ECU being output?
YES Go to relevant DTC chart.
NO
2 Are there any other codes (Desides DTC P3009) being output?
YES Go to relevant DTC chart.
NO
DI82A±01

± 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

DI±334
± DIAGNOSTICSHV BATTERY CONTROL SYSTEM
2001 PRIUS (RM778U) 4/27/01
5 Check insulating resistance of power cable.
PREPARATION:
(a) Under step 3 condition, turn the ignition switch OFF and disconnect the negative terminal of the auxilia-
ry battery.
(b) Remove the service plug.
(c) Disconnect the 2 power cables from the converter & inverter.
(d) Disconnect the 2 power cables from the HV battery.
CHECK:
Using a megger (500V), measure the insulating resistance between the power cable and body ground.
OK:
Insulating resistance: 10MW or more
NG Replace the power cable.
OK
6 Check insulating resistance of power cable of hybrid transaxle.
PREPARATION:
(a) Under step 4 condition, disconnect the 3 power cables for MG2 and a power cable for MG1 from the
converter & inverter assembly.
(b) Check that the voltage between each of the 6 terminals of the power cables and body ground is 0 V.
CHECK:
Using a megger (500V), measure the insulating resistance between each of the 6 terminals and the hybrid
transaxle.
OK:
Insulating resistance: 10MW or more
NG Replace the hybrid transaxle assembly.
OK

± DIAGNOSTICSHV BATTERY CONTROL SYSTEM
DI±335
2001 PRIUS (RM778U)
7 Check insulating resistance of converter & inverter assembly.
CHECK:
Using a megger (500V), measure the insulating resistance between each of 2 connected parts of the HV
battery power cables to the converter & inverter and the converter & inverter itself, and between each of 6
connected parts of MG2/MG1 power cables to the converter & inverter and the converter & inverter itself.
and the hybrid transaxle.
OK:
Insulating resistance: 0.9MW
NG Replace the converter & inverter assembly.
OK
Replace the battery ECU.

DI±336
± DIAGNOSTICSHV BATTERY CONTROL SYSTEM
2001 PRIUS (RM778U) 4/27/01
8 Is DTC P3009 of battery ECU being output?
(Check for battery cover.)
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) Remove the 2 bolts and power cables.
(f) Remove the battery cover.
(g) Connecting the negative terminal of the auxiliary battery, turn the ignition switch ON and clear the 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.
(h) After turning the ignition switch OFF, connect the service plug.
(i) 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