TOYOTA AVENSIS 2005 Service Repair Manual

C52361
TcCGDLC3:
±
DIAGNOSTICS ELECTRONIC MOTOR POWER STEERING SYSTEM
05±1085
AVENSIS REPAIR MANUAL (RM1018E)
INSPECTION PROCEDURE
1INSPECT DLC3 TERMINAL VOLTAGE(Tc TERMINAL)
(a)Turn the ignition switch ON.
(b)Measure the voltage between terminals Tc and CG of
DLC3.
OK:
Voltage: 5 to 16 V
OKGo to step 3
NG
2CHECK HARNESS AND CONNECTOR(DLC3 ± BODY GROUND)
(a)Check for an open or short circuit in harness and connector between terminals\
CG of DLC3 and body ground (See page 01±32).
NG REPAIR OR REPLACE HARNESS ORCONNECTOR
OK
3 CHECK HARNESS AND CONNECTOR(DLC3 ± POWER STEERING ECU ASSY)
(a) Check for an open or short circuit in harness and connector between terminals\
Tc of DLC3 and power steering ECU assy (See page 01±32).
NG REPAIR OR REPLACE HARNESS ORCONNECTOR
OK
REPLACE POWER STEERING ECU ASSY(See page 50±20)

F44861
B±W22
C11Combination Meter
Driver Side J/B
Engine Room R/B No.4 Engine Room R/B No.1 and
Engine Room J/B No.1Power Steering
ECU Assy
6
C11
17
C10B±W
W±B
W±B
B±WP/S
J8C
AM2 J26A
J8C
J26A J/C
B±WB±R
B±R B±R B±R
B±RB±GB±G
B±G (*1) (*2) (*1) (*2)(*1)
(*2)
18
DA2
DH IGN
IE41
IP11
(*1) (*2)
1
1A1
111
4A
4B
2AM2 IG2 I13
Ignition SWE159
WL
46
FL MAIN
BatteryJ15
J/CJ16
J/C
IK
IO AA
*1: LHD
*2: RHDA
AJ17
J/C
A W±B
(*2)
W±B
(*1) 05±1082
± DIAGNOSTICSELECTRONIC MOTOR POWER STEERING SYSTEM
AVENSIS REPAIR MANUAL (RM1018E)
EMPS Warning Light Circuit
CIRCUIT DESCRIPTION
If the power steering ECU assy detects a trouble, the PS warning lights up. At this time, the power steering
ECU assy records a DTC in memory.
WIRING DIAGRAM
05C5I±01

F44851
E14PGND
F44869
E15WL
±
DIAGNOSTICS ELECTRONIC MOTOR POWER STEERING SYSTEM
05±1083
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.
1CHECK HARNESS AND CONNECTOR(POWER STEERING ECU ASSY ±
COMBINATION METER ASSY)
(a)Check for an open or short circuit in harness and connector between power ste\
ering ECU assy and
combination meter assy (See page 01±32).
NGREPAIR OR REPLACE HARNESS ORCONNECTOR
OK
2CHECK HARNESS AND CONNECTOR(POWER STEERING ECU ASSY ± BODY GROUND)
(a)Disconnect the E14 connector from the power steering
ECU assy.
(b)Check the continuity between the terminal PGND of the
E14 connector and body ground.
Standard:
Continuity
NGREPAIR OR REPLACE HARNESS OR CONNECTOR
OK
3INSPECT POWER STEERING ECU ASSY
(a)Turn the ignition switch ON.
(b)Disconnect the E15 connector from the power steering ECU assy, and check the P/S warning light comes on.
(c)Using a service wire, ground the terminal WL of the E15 connector, and check the P/S warning light goes off.
Standard:
P/S warning light comes on and then goes off
NGREPLACE POWER STEERING ECU ASSY (See page 50±20)
OK
CHECK GO TO COMBINATION METER SYSTEM

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

F45794
1
2
533
5 1
2
F44851
PGND
E14
05±1078
± DIAGNOSTICSELECTRONIC MOTOR POWER STEERING SYSTEM
AVENSIS REPAIR MANUAL (RM1018E)
2 INSPECT EMPS RELAY
(a) Remove the EMPS relay from the engine room R/B No.
1 and J/B No. 1.
(b) Check operation of the EMPS relay.
Standard:
Terminal No.Specified condition
3 ± 510 k or higher
3 ± 5Below 1 

When battery voltage is applied to terminals 1 and 2)
NG REPLACE EMPS RELAY
OK
3 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 the terminal PGND of
the E14 connector and body ground.
Standard:
Resistance: 1  or less
NG REPAIR OR REPLACE HARNESS OR
CONNECTOR
OK

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)

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