Page 1129 of 5135
F44851
E14
PIG (+)
PGND (±)
±
DIAGNOSTICS ELECTRONIC MOTOR POWER STEERING SYSTEM
05±1079
AVENSIS REPAIR MANUAL (RM1018E)
4CHECK HARNESS AND CONNECTOR(POWER STEERING ECU ASSY ± ENGINE
ROOM R/B AND J/B)
(a)Disconnect the E14 connector from the power steering
ECU assy.
(b)Turn the ignition switch ON.
(c)Measure the voltage between the terminals PIG and PGND of the E14 connector.
Standard:
Voltage: 10 to 16 V
NGREPAIR OR REPLACE HARNESS OR CONNECTOR
OK
REPLACE POWER STEERING ECU ASSY(See page 50±20)
Page 1130 of 5135
F44867
Engine Room R/B No. 4 I13
Ignition SWDriver Side J/B
ECU±IG
AM1
ALT
FL MAIN
BatteryIG1Relay
AM1 IG1IG
PGND R±W
R±WR±W
W±B
W±B
W±B B±G B±GG±Y
G±RJ10G
J20C
J11G
J21C
E156
E142 DB 18
DH5
DH1
DN1 DA9
4B1
4D1
IJ IM 12125 3
31J/C
(*1)
(*2)(*1)
(*2)
*1: LHD
*2: RHDPower Steering
ECU Assy
± DIAGNOSTICSELECTRONIC MOTOR POWER STEERING SYSTEM
05±1073
AVENSIS REPAIR MANUAL (RM1018E)
DTC C1551/51 IG Power Source Circuit Malfunction
CIRCUIT DESCRIPTION
The power steering ECU assy identifies ON or OFF status of the ignition switch by this circuit.
DTC No.DTC Detecting ConditionTrouble Area
C1551/51Unusual IG voltage value which exceeds the specification is
inputed to power steering ECU assy.
ECU±IG fuse
IG power source circuit
Charging system
Power steering ECU assy
WIRING DIAGRAM
0579N±02
Page 1131 of 5135
F44856
ECU±IG
Fuse Driver Side J/B:
F44851
PGND (±)
E14
05±1074
± DIAGNOSTICSELECTRONIC MOTOR POWER STEERING SYSTEM
AVENSIS REPAIR MANUAL (RM1018E)
INSPECTION PROCEDURE
NOTICE:
When performing the inspection of power steering ECU, ECU must be installed to the vehicle or fully
fixed.
1 INSPECT FUSE(ECU±IG)
(a) Remove the ECU±IG fuse from the driver side J/B.
(b) Check the continuity of the ECU±IG fuse.
Standard:
Continuity
NG INSPECT FOR SHORT CIRCUIT IN ALL
HARNESS AND COMPONENTS CONNECTED
TO ECU±IG FUSE
OK
2 CHECK HARNESS AND CONNECTOR(POWER STEERING ECU ASSY ± BODY
GROUND)
(a) Disconnect the E14 connector from the power steering
ECU assy.
(b) Measure the resistance between terminal PGND of E14
connector and body ground.
Standard:
Resistance: 1 or less
NG REPAIR OR REPLACE HARNESS OR
CONNECTOR
OK
Page 1132 of 5135
F44855
PGNDE14
IG E15
±
DIAGNOSTICS ELECTRONIC MOTOR POWER STEERING SYSTEM
05±1075
AVENSIS REPAIR MANUAL (RM1018E)
3CHECK HARNESS AND CONNECTOR(POWER STEERING ECU ASSY ± DRIVER
SIDE J/B)
(a)Disconnect the E14 and E15 connectors from the power
steering ECU assy.
(b)Turn the ignition switch ON.
(c)Measure the voltage between terminals IG and PGND of the E14 and E15 connectors.
Standard:
Voltage: 10 to 16 V
NGREPAIR OR REPLACE HARNESS OR CONNECTOR
OK
REPLACE POWER STEERING ECU ASSY (See page 50±20)
Page 1133 of 5135
F44865
ECMPower Steering ECU
TACH E95
(*1) GR±R
(*2) (*1) (*2)GR±R
J9A
J27B
J9A
J27B
E1512
*1: LHD
*2: RHDJ/C
TACH 05±1070
± DIAGNOSTICSELECTRONIC MOTOR POWER STEERING SYSTEM
AVENSIS REPAIR MANUAL (RM1018E)
DTC C1544/44 Engine Revolution Signal Malfunction
DTC C1545/45 Engine Revolution Signal Malfunction
DTC C1573/73 Engine Revolution Signal Malfunction (Test
Mode)
CIRCUIT DESCRIPTION
DTC No.DTC Detecting ConditionTrouble Area
C1544/44Engine revolution signal malfunctionEngine revolution signal circuit
C1545/45Engine revolution signal malfunctionEngine revolution signal circuit
ECM
C1573/73Engine revolution signal malfunction (Test mode)Power steering ECU assy
WIRING DIAGRAM
0579M±02
Page 1134 of 5135

±
DIAGNOSTICS ELECTRONIC MOTOR POWER STEERING SYSTEM
05±1071
AVENSIS REPAIR MANUAL (RM1018E)
INSPECTION PROCEDURE
NOTICE:
When performing the inspection of power steering ECU, ECU must be instal\
led to the vehicle or fully
fixed.
HINT:
Start the inspection from the step 1 with using hand±held tester. Start from step 2 without using hand±held
tester.
1READ VALUE OF HAND±HELD TESTER
(a)Connect the hand±held tester to the DLC3.
(b)Turn the ignition switch to ON, and turn the hand±held tester main swi\
tch to ON.
(c)Select the item ºENGINE REVº in the DATA LIST and read its value displayed on the hand±held tester.
(d)Check that there is no difference between the engine revolution value output from the tachometer d\
is-
played by the hand±held tester and the engine revolution value displayed by\
the tachometer when
engine is idle.
OK:
There is almost no difference in the displayed engine revolution values.\
HINT:
There is tolerance of 10 % in the tachometer indication.
OKREPLACE POWER STEERING ECU ASSY(Seepage 50±20)
NG
2 CHECK DIAGNOSTIC CODE OUTPUT
(a) Check that the DTC for engine output the normal code. NG REPAIR CIRCUIT INDICATED BY OUTPUTCODE
OK
Page 1135 of 5135
F44304
PGNDE14TACH
E15
A05138
5 V/
Division
10 ms / Division
05±1072
±
DIAGNOSTICS ELECTRONIC MOTOR POWER STEERING SYSTEM
AVENSIS REPAIR MANUAL (RM1018E)
3INSPECT POWER STEERING ECU ASSY(ENGINE REVOLUTION SIGNAL)
(a)Turn the ignition switch ON.
(b)Connect an oscilloscope to terminals TACH and PGND of the power steering ECU assy connector.
(c)With the engine idling, check the signal waveform. Standard:
Signal waveform as shown in the illustration.
HINT:
As the engine revolution becomes high, the waveform cycle
narrows.
OKREPLACE POWER STEERING ECU ASSY(See page 50±20)
NG
4 CHECK HARNESS AND CONNECTOR(POWER STEERING ECU ASSY ± ECM)
(a) Check for an open or short circuit in harness and connector between powe\
r steering ECU assy and ECM (See page 01±32).
NG REPAIR OR REPLACE HARNESS ORCONNECTOR
OK
GO TO ENGINE CONTROL SYSTEM
Page 1136 of 5135
F44865
Combination Meter Power Steering ECU
C11V±W 18
SPD J10H
J10H
J20H
J20H
E155
V±W
(*1) (*2) (*1) (*2)
*1: LHD
*2: RHDJ/C
± DIAGNOSTICSELECTRONIC MOTOR POWER STEERING SYSTEM
05±1067
AVENSIS REPAIR MANUAL (RM1018E)
DTC C1541/41 Speed Sensor Malfunction
DTC C1542/42 Speed Sensor Malfunction
DTC C1571/71 Speed Sensor Malfunction (Test mode)
CIRCUIT DESCRIPTION
DTC No.DTC Detecting ConditionTrouble Area
C1541/41
Speed sensor malfunction
Speed sensor
Speed sensor circuit
C1542/42
Speed sensor malfunctionSpeed sensor circuit
Skid control ECU assy
Cbiti tC1571/71Speed sensor malfunction (Test mode)Combination meter assy
Power steering ECU assy
WIRING DIAGRAM
0579L±02