2005 TOYOTA AVENSIS Circuit

F44862
Engine Room R/B No.1 and
Engine Room J/B No.1Power Steering
ECU Assy
Engine Room R/B No.4 EMPS Relay
W±R
FL MAIN
BatteryPIG
RLY
PGND R
R
RIE1L
1 1 11
1
1A
1 22 1
1
EMPS 53
51
E14
3
E15
2
E14 W±R
W±B
B±G
4B1
4A1
IM B±G 05±1080
± DIAGNOSTICSELECTRONIC MOTOR POWER STEERING SYSTEM
AVENSIS REPAIR MANUAL (RM1018E)
DTC C1555/55 EMPS Motor Relay Circuit
CIRCUIT DESCRIPTION
If a malfunction occurs in the system, the system prohibits the steering assist by interrupting the circuits of
the EMPS relay and the motor relay (built in the power steering ECU assy).
DTC No.DTC Detecting ConditionTrouble Area
C1555/55Open or short circuit of EMPS motor relay in the ECU circuit is
detected.Power steering ECU assy
WIRING DIAGRAM
0579Q±02

F44304
PGND (±)
E14PIG (+)
±
DIAGNOSTICS ELECTRONIC MOTOR POWER STEERING SYSTEM
05±1081
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 swit\
ch to ON.
(c)Select the item ºPIG SUPPLYº in the FREEZE FRAME DATA and read its value displayed on the hand±
held tester.
(d)Check that the power supply voltage value of the drive motor displayed b\
y the hand±held tester. Standard:
Voltage: 10 to 16 V
OKGo to step 3
NG
GO TO RELEVANT DTC CHART
2INSPECT POWER STEERING ECU ASSY(PIG TERMINAL VOLTGE)
(a)Turn the ignition switch ON.
(b)Measure the voltage between terminals PIG and PGND of power steering ECU assy connector.
Standard:
Voltage: 10 to 16 V
NGGO TO RELEVANT DTC CHART (See page 05±1076)
OK
3 RECONFIRM DTC
(a)Check the DTCs (See page 05±1045).
(b) Is DTC except for C1552/52 output? YES REPAIR CIRCUIT INDICATED BY OUTPUTCODE
NO
REPLACE POWER STEERING ECU ASSY(See page 50±20)

F44862
Engine Room R/B No.1 and Engine Room J/B No.1Power Steering
ECU Assy
Engine Room R/B No.4 EMPS Relay
W±R
FL MAIN
BatteryPIG
RLY
PGND R
R
RIE1L
1 1 1
1
1
1A
1 22 1
1
EMPS 53
51
E14
3
E15
2
E14 W±R
W±B
B±G
4B1
4A1
IM B±G 05±1076
± DIAGNOSTICSELECTRONIC MOTOR POWER STEERING SYSTEM
AVENSIS REPAIR MANUAL (RM1018E)
DTC C1552/52 PIG Power Source Circuit
DTC C1554/54 EMPS Relay Circuit
CIRCUIT DESCRIPTION
When turning the ignition switch to ON, battery voltage is supplied to terminal PIG of the power steering ECU
assy by EMPS relay operations. If a malfunction occurs in the system, the system prohibits the steering as-
sist by interrupting the circuits of the EMPS relay and the motor relay (built in the power steering ECU assy).
DTC No.DTC Detecting ConditionTrouble Area
C1552/52Unusual motor power source voltage value which is not within
the specification is input to power steering ECU assy.
EMPS fuse

EMPS relay

PIG power source circuitC1554/54Open or short circuit of EMPS relay circuit is detected.
PIG power source circuit

Power steering ECU assy
WIRING DIAGRAM
0579O±02

F44852
Engine Room R/B No.1 and
Engine Room J/B No.1:
EMPS
Fuse
EMPS Relay
± DIAGNOSTICSELECTRONIC MOTOR POWER STEERING SYSTEM
05±1077
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(EMPS)
(a) Remove the EMPS fuse from the engine room R/B No.1
and J/B No.1.
(b) Check the continuity of the EMPS fuse.
Standard:
Continuity
NG INSPECT FOR SHORT CIRCUIT IN HARNESS
AND ALL COMPONENTS CONNECTED TO
EMPS FUSE
OK

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

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

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 malfunction
Engine revolution signal circuit
C1545/45Engine revolution signal malfunction
Engine revolution signal circuit

ECM
C1573/73Engine revolution signal malfunction (Test mode)
Power steering ECU assy
WIRING DIAGRAM
0579M±02

±
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