2001 TOYOTA PRIUS Service Repair Manual

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

F12396
TOYOTA
Hand±held Tester
DLC3
F12848
Tc
CG
Ts
F12871
Malfunction Code (Example Code 72)
7
2
ON
OFF
0.5 sec. 0.5 sec.
0.5 sec.
1.5 sec.4 sec.
Repeat
0.5 sec. ON
OFF
0.25 sec.
0.25 sec. Normal Code
A Cycle
± DIAGNOSTICSELECTRIC MOTOR POWER STEERING
DI±461
2001 PRIUS (RM778U)
(e) In case of using TOYOTA hand±held tester:
Clear the DTC.
(1) Hook up the TOYOTA hand±held tester to the
DLC3.
(2) Turn the ignition switch ON.
(3) Operate the TOYOTA hand±held tester to erase the
codes. (See TOYOTA hand±held tester operator's
manual.)
2. INPUT SIGNAL CHECK (TEST MODE)
(a) In case of not using TOYOTA hand±held tester:
Check the input signal.
(1) Turn the ignition switch OFF.
(2) Using SST, connect terminals Ts and CG of DLC3.
SST 09843±18040
(3) Check the warning light goes off with driving more
than 20 km/h (12 mph).
HINT:
If the warning light goes off during driving, the sensor can be
judged to normal.
(4) Stop the vehicle.
(5) Using SST, connect terminals Tc and CG of DLC3.
SST 09843±18040
(6) Read the number of blinks of the PS warning light.
HINT:

See the list of DTC shown on the next page.

Even a sensor is normal, it output codes 71 and 72 during
test mode.
(7) After doing check, disconnect the SST from the ter-
minals Ts and CG, Tc and CG of DLC3, and turn the
ignition switch OFF.
SST 09843±18040

F12396
TOYOTA
Hand±held Tester
DLC3
DI±462
± DIAGNOSTICSELECTRIC MOTOR POWER STEERING
2001 PRIUS (RM778U)
(b) In case of using TOYOTA hand±held tester:
Check the input signal.
(1) Hook up the TOYOTA hand±held tester to the
DLC3.
(2) Check the warning light goes off with driving more
than 20 km/h (12 mph).
(3) Read the DTC by following the prompts on the tes-
ter screen.
HINT:

Please refer to the TOYOTA hand±held tester operator's
manual for further details.

See the list of DTC shown on the bottom of this page.

Even a sensor is normal, it output codes 71 and 72 during
test mode.
DTC of input signal check function:
Code No.
(See page)DiagnosisTrouble Area
C1515/15
(DI±468)Calibration of torque sensor zero point Not Performed±
C1516/16
(DI±469)Calibration of torque sensor zero point Not completed±
C1571/71
C1572/72
(DI±474)
Speed sensor malfunction (Test mode)

Right rear or left rear speed sensor

Sensor installation

Right rear or left rear speed sensor rotor

Right rear or left rear speed sensor circuit

Brake ECU

EMPS ECU
3. CALIBRATION OF TORQUE SENSOR ZERO POINT
HINT:
Perform this operation in the following cases.

When removing and installing ºsteering wheelº, ºtilt steer-
ing columnºand ºelectric power steering gearº.

When replacing EMPS ECU.
(a) Place front wheels and steering wheel facing straight
ahead.
(b) In case of using TOYOTA hand±held tester:
Perform the torque sensor zero point initialization.
HINT:
If the EMPS ECU is replaced, however, this operation is not
necessary.
(1) Stop the vehicle.