2001 TOYOTA PRIUS display

F12405
ON
IG1
GND
F12406
LOCK
GNDB11
B10
DI±404
± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM WITH EBD & RBS
2001 PRIUS (RM778U)
3 Check voltage of the ECU IG power source.
In case of using the TOYOTA hand±held tester:
PREPARATION:
(a) Connect the TOYOTA hand±held tester to the DLC3.
(b) Turn the ignition switch ON, and push the TOYOTA hand±held tester main switch ON.
(c) Select the DATALIST mode on the TOYOTA hand±held tester.
CHECK:
Check the voltage condition output from the ECU displayed on the TOYOTA hand±held tester.
OK:
ºNormalº is displayed.
In case of not using the TOYOTA hand±held tester:
PREPARATION:
Remove the brake ECU with connectors still connected.
CHECK:
Turn the ignition switch ON, measure voltage between termi-
nals IG1 and GND of brake ECU connector.
OK:
Voltage: 10 ± 14 V
OK Check and replace brake ECU.
NG
4 Check continuity between terminal GND of brake ECU connector and body
ground.
PREPARATION:
Disconnect the 2 connectors (B10, B11) from the brake ECU.
CHECK:
Measure resistance between terminal GND of brake ECU har-
ness side connector and body ground.
OK:
Resistance: 1 W or less
NG Repair or replace harness or connector.
OK
Check for open circuit in harness and connector between brake ECU and battery (See page
IN±41).

F10935
ON
IG2
GND
DI±406
± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM WITH EBD & RBS
2001 PRIUS (RM778U)
INSPECTION PROCEDURE
1 Check battery positive voltage.
OK:
Voltage: 10 ± 14 V
NG Check and repair the charging system (See
page HV±39).
OK
2 Check voltage of the ECU IG power source.
In case of using the TOYOTA hand±held tester:
PREPARATION:
(a) Connect the TOYOTA hand±held tester to the DLC3.
(b) Turn the ignition switch ON, and push the TOYOTA hand±held tester main switch ON.
(c) Select the DATALIST mode on the TOYOTA hand±held tester.
CHECK:
Check the voltage condition output from the ECU displayed on the TOYOTA hand±held tester.
OK:
ºNormalº is displayed.
In case of not using the TOYOTA hand±held tester:
PREPARATION:
Remove the brake ECU with connectors still connected.
CHECK:
Turn the ignition switch ON, measure voltage between termi-
nals IG2 and GND of brake ECU connector.
OK:
Voltage: 10 ± 14 V
OK Check and replace brake ECU.
NG

F12405
ON
IG1
GND
F12406
LOCK
GNDB11
B10
± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM WITH EBD & RBS
DI±437
2001 PRIUS (RM778U)
3 Check voltage of the ECU IG power source.
In case of using the TOYOTA hand±held tester:
PREPARATION:
(a) Connect the TOYOTA hand±held tester to the DLC3.
(b) Turn the ignition switch ON, and push the TOYOTA hand±held tester main switch ON.
(c) Select the DATALIST mode on the TOYOTA hand±held tester.
CHECK:
Check the voltage condition output from the ECU displayed on the TOYOTA hand±held tester.
OK:
ºNormalº is displayed.
In case of not using the TOYOTA hand±held tester:
PREPARATION:
Remove the brake ECU with connectors still connected.
CHECK:
Turn the ignition switch ON, measure voltage between termi-
nals IG1 and GND of brake ECU connector.
OK:
Voltage: 10 ± 14 V
OK Check and replace brake ECU.
NG
4 Check continuity between terminal GND of brake ECU connector and body
ground.
PREPARATION:
Disconnect the 2 connectors (B10, B11) from the brake ECU.
CHECK:
Measure resistance between terminal GND of brake ECU har-
ness side connector and body ground.
OK:
Resistance: 1 W or less
NG Repair or replace harness or connector.
OK
Check for open circuit in harness and connector between brake ECU and battery (See page
IN±41).

DI±440
± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM WITH EBD & RBS
2001 PRIUS (RM778U)
INSPECTION PROCEDURE
1 Check that brake ECU connectors are securely connected to brake ECU.
NO Connect connectors to brake ECU.
YES
2 Is DTC output?
Check DTC on page DI±353.
YES Repair circuit indicated by output code.
NO
3 Is normal code displayed?
YES Check ABS solenoid relay. Check for short cir-
cuit in harness and connector between ABS so-
lenoid relay and DLC3 (See page IN±41).
NO
4 Does ABS warning light go off?
YES Check for open or short circuit in harness and
connector between ECU±IG fuse and brake ECU
(See page IN±41).
NO

F12686
DLC3
2DTc 3
Tc
8
4 CG13ID1 P±B P±B
B11
W±B
AJ11
J/C
A
ID C
Instrument Panel J/BBrake ECU
J16
J/C J26
J/C
J24
J/CP±B P±B
E E
C
W±B W±B
A2K 82
F09678
CG TcDLC3 ON
(+) (±)
DI±452
± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM WITH EBD & RBS
2001 PRIUS (RM778U)
Tc Terminal Circuit
CIRCUIT DESCRIPTION
Connecting terminals Tc and CG of the DLC3 causes the ECU to display the DTC by flashing the ABS warn-
ing light.
WIRING DIAGRAM
INSPECTION PROCEDURE
1 Check voltage between terminals Tc and CG of DLC3.
PREPARATION:
Turn the ignition switch ON.
CHECK:
Measure voltage between terminal Tc and CG of DLC3.
OK:
Voltage: 10 ± 14 V
OK If ABS warning light does not blink even after Tc
and CG are connected, the ECU may be defec-
tive.
NG
DI29I±13

DI7QW±01
F12845
F12874
F12846
Tc
CG
F12873
WL
PGND
± DIAGNOSTICSELECTRIC MOTOR POWER STEERING
DI±459
2001 PRIUS (RM778U)
PRE±CHECK
1. DIAGNOSIS SYSTEM
(a) Check the indicator.
When the ignition switch is turned ON, check that the PS
warning light goes on for 1.5 seconds.
HINT:

If the indicator check result is not normal, proceed to trou-
bleshooting for the PS warning light circuit (See page
DI±486).

When the EMPS system is faulty, the master warning light
in the combination meter and the PS warning light in the
multiinformation display lights up.
(b) In case of not using TOYOTA hand±held tester:
Check the DTC.
(1) Using SST, connect terminals Tc and CG of the
DLC3.
SST 09843±18040
(2) Remove the EMPS ECU with connector still con-
nected.
(3) Connect the both terminals of the 1kW resistance
and LED (Light Emitting Diode) circuit to terminals
WL and PGND of the EMPS ECU.
(4) Turn the ignition switch ON.
(5) Read the DTC from the PS warning light.

F12870
Normal Code
0.25 sec.
0.25 sec.
ON
OFF
ON
OFF0.5 sec.
0.5 sec.
Codes 21 and 22
1.5 sec.2.5 sec.
Code 21Code 22
4 sec.0.5 sec.
F12396
TOYOTA
Hand±held Tester
DLC3
F12861
Ts
CG
DI±460
± DIAGNOSTICSELECTRIC MOTOR POWER STEERING
2001 PRIUS (RM778U)
HINT:

If no code appears, inspect the diagnostic circuit and PS
warning light circuit (See page DI±491 or DI±486).

As an example, the blinking patterns for normal code and
codes 21 and 22 are shown on the left.
(6) Codes are explained in the DTC chart on page
DI±460.
(7) After completing the check, disconnect terminals Tc
and CG of the DLC3, and turn off the display.
If 2 or more malfunctions are indicated at the same
time, the lowest numbered DTC will be displayed
first.
(c) In case of using TOYOTA hand±held tester:
Check the DTC.
(1) Hook up the TOYOTA hand±held tester to the
DLC3.
(2) Turn the ignition switch ON.
(3) Read the DTC by following the prompts on the tes-
ter screen.
HINT:
Please refer to the TOYOTA hand±held tester operator's manu-
al for further details.
(d) In case of not using TOYOTA hand±held tester:
Clear the DTC.
(1) Using SST, connect terminals Ts and CG of DLC3.
SST 09843±18040
(2) Turn the ignition switch ON.
(3) ON and OFF the terminal CG of the DLC3 4 times
or more within 8 seconds, delete DTC of the EMPS
ECU.
(4) Check that the PS warning light shows the normal
code.
(5) Remove the SST from the DLC3.
SST 09843±18040

DI7QX±01
± DIAGNOSTICSELECTRIC MOTOR POWER STEERING
DI±465
2001 PRIUS (RM778U)
DIAGNOSTIC TROUBLE CODE CHART
HINT:

Using SST 09843±18040, connect terminals Tc and CG of the DLC3.

If a malfunction code is displayed during the DTC check, check the circuit listed for the code. For details
of each code, turn to the page referred to under the ºSee pageº for respective ºDTC No.º in the DTC
chart.
DTC No.
(See page)Detection ItemTrouble Area
C1511/11
(DI±465)
C1512/12
(DI±465)
T i it lf ti
Torque sensor
C1513/13
(DI±465)Torque sensor circuit malfunction
Torque sensor

EMPS ECU
C1514/14
(DI±465)
C1521/21
(DI±471)
C1522/22
(DI±471)
Mt i it lf ti
Power steering gear assembly with motor
C1523/23
(DI±471)Motor circuit malfunction
Power steering gear assembly with motor

EMPS ECU
C1524/24
(DI±471)
C1531/31
(DI±473)
C1532/32
(DI±473)EMPS ECU malfunctionEMPS ECU
C1533/33
(DI±473)
C1541/41
(DI±474)
C1542/42
(DI±474)Speed sensor malfunction

Speed sensor

Brake ECU

EMPS ECUC1543/43
(DI±474)
EMPS ECU
C1551/51
(DI±476)IG power source circuit malfunction

EMPS ECU

Power source circuit

Charging system
C1552/52
(DI±479)PIG power source drop voltage malfunction
EMPS ECU

Power source circuit
C1553/53
(DI±482)When resetting voltage, vehicle is being drivenEMPS ECU
C1554/54
(DI±483)EMPS relay circuit malfunction

EMPS relay

EMPS ECU

EMPS relay circuit
C1555/55
(DI±473)EMPS ECU malfunctionEMPS ECU
C1556/56
(DI±486)P/S warning light circuit
Multiinformation display

EMPS ECU