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Scan Tool DataS6RW0D6304007
NOTE
When P/S motor is cold condition (that is, armature coil of P/S motor is not heated), normal value with
asterisk (*) mark in the following table is displayed on scan tool
Scan Tool Data Definitions
Power Supply Voltage
This parameter indicates battery positive voltage.
Sensor Power Supply (Torque Sensor Power Supply,
V)
This parameter indicates the power supply voltage which
the P/S control module supplies to the torque sensor.
Sensor (Main) Torque (Torque Sensor Main Torque,
N⋅m)
The torque sensor is installed to detect the steering force
and the steering direction. It consists of two
potentiometers and the main torque sensor is one of
these.
Sensor (Sub) Torque (Torque Sensor Sub Torque,
N⋅m)
The torque sensor is installed to detect the steering force
and the steering direction. It consists of two
potentiometers and the sub-torque sensor is one of
these. Its output characteristics are compared with those
of the main torque sensor.Control Torque (N⋅m)
This parameter is an internal parameter of the P/S
control module. It is obtained by computing the torque
sensor input signal.
Target Motor Current (Motor Control Current, A)
Based on the input signal, the P/S control module
determines the assist amount and controls the current to
the motor suitable for that assist amount. This parameter
indicates that control value.
Measured MOT Current (Motor Monitor Current, A)
This parameter indicates the actually measured value of
the current flowing to the motor. The motor circuit
condition is diagnosed by comparing this parameter with
“Motor Control” parameter described previously.
Vehicle Speed (km/h, MPH)
Vehicle speed signal is fed from BCM. P/S control
module determines the amount of power assist based on
this vehicle speed signal and the torque sensor signal.
Engine Speed (rpm)
Engine speed signal is fed from the ECM so that it can
be used for trouble diagnosis of the electric power
steering system. Scan tool data Vehicle condition Normal condition
) Power Supply Voltage
Ignition switch ON10 – 14 V
) Sensor Power Supply7.4 – 10 V
) Sensor (Main) TorqueEngine running at idle
speedSteering wheel at fully turned to left –10.5 – 0 N⋅m
Steering wheel at free 0 N⋅m
Steering wheel at fully turned to right 0 – 12.85 N⋅m
) Sensor (Sub) Torque Engine running at idle
speedSteering wheel at fully turned to left 0 – 10.65 N⋅m
Steering wheel at free 0 N⋅m
Steering wheel at fully turned to right –12.85 – 0 N⋅m
) Control TorqueEngine running at idle
speedSteering wheel at fully turned to left –7.22 – 0 N⋅m
Steering wheel at free 0 N⋅m
Steering wheel at fully turned to right 0 – 7.16 N⋅m
) Target Motor CurrentEngine running at idle
speedSteering wheel at free 0 A
Steering wheel at fully turned to left or
right*45 – 60 A
) Measured MOT
Current
Engine running at idle
speedSteering wheel at free 0 A
Steering wheel at fully turned to left or
right*45 – 60 A
) Vehicle Speed Engine running and vehicle at stop 0 km/h
) Engine Speed Engine running at idle speed after warming up 700 ± 50 rpm
) Motor Drive VoltageEngine running at idle
speedSteering wheel at free 0.8 – 1 V
Steering wheel at fully turned to right *5.5 – 8.5 V
) System Power Status
Ignition switch ONON
) IGN switch StatusON
) Torque sensor Status
Engine running at idle speedON
) Fail Safe FET StatusON
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Motor Drive Voltage (V)
This parameter indicates the voltage between motor
terminals.
System Power Status (EPS System Power, ON, OFF)
This parameter indicates input status of EPS system
power supply.
IGN switch Status (ON, OFF)
This parameter indicates the condition of the power
supply through the ignition switch.Torque sensor Status (ON, OFF)
This parameter indicates the output status of the torque
sensor power supply.
Fail Safe FET Status (ON, OFF)
This parameter indicates the status of the motor drive
power supply circuit.
P/S System Symptom DiagnosisS6RW0D6304008
This section describes trouble diagnosis of the P/S system parts whose trouble is not indicated by the on-board
diagnostic system (self-diagnostic function). When no malfunction is indicated by the on-board diagnostic system
(self-diagnosis function) and assuredly those steering basic parts as described in “Steering Symptom Diagnosis in
Section 6A” are all in good condition, check the following power steering system parts which may be a possible cause
for each symptom of the steering.
Condition Possible cause Correction / Reference Item
Steering wheel feels
heavy (Perform “Steering
Force Check:” before
diagnosis.)Steering wheel installed improperly
(twisted)Install steering wheel correctly.
Poor performance of P/S motorCheck P/S motor referring to “P/S Motor and
Its Circuit Inspection”.
Poor performance of torque sensorCheck torque sensor referring to “Torque
Sensor and Its Circuit Inspection”.
Steering gear case assembly
malfunctionReplace steering gear case assembly.
Poor performance of vehicle speed
signal from BCMCheck vehicle speed signal circuit referring to
“DTC C1121 / C1123 / C1124: Vehicle Speed
Signal Circuit Failure”.
Steering wheel feels
heavy momentarily when
turning it to the left or
rightSteering gear case assembly
malfunctionReplace steering gear case assembly.
Poor recovery from turnsPoor performance of torque sensorCheck torque sensor referring to “Torque
Sensor and Its Circuit Inspection”.
Steering gear case assembly
malfunctionReplace steering gear case assembly.
Vehicle pulls to one side
during straight drivingPoor performance of torque sensorCheck torque sensor referring to “Torque
Sensor and Its Circuit Inspection”.
Steering gear case assembly
malfunctionReplace steering gear case assembly.
Abnormal noiseP/S motor (built in steering gear case
assembly) malfunctionReplace steering gear case assembly.
No idle upP/S control module faultyCheck P/S control module referring to
“Inspection of P/S Control Module and Its
Circuits”.
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DTC C1141 / C1142 / C1143 / C1145: Motor Circuit FailureS6RW0D6304016
DTC C1141: P/S Motor Circuit Voltage
DTC C1142: P/S Motor Circuit Range/Performance
DTC C1143: P/S Motor Circuit Current Too High
DTC C1145: P/S Motor Circuit Current Too Low
Wiring Diagram
DTC Detecting Condition and Trouble Area
[A]
123
4567
8
9 11
10 12 13
141516
17 18 1920
1
2
[B]
1
2
[C]
LT GRN/
BLK
BLK
RED
E11-1
E12-1
E12-2 E13-1 GRNGRN
WHT
5
6 3 7
9
10
8
4 12
12V
E13-2BLK
E61-2
E61-1
11
I6RW0C630008-01
[A]: P/S control module connector No.1 “E11” (viewed from harness side) 2. Ignition switch 7. Individual circuit fuse box No.1
[B]: P/S control module connector No.2 “E13” (viewed from harness side) 3. Junction block assembly 8. “IGN” fuse
[C]: P/S control module connector No.3 “E12” (viewed from harness side) 4. Main fuse 9. “P/S” fuse
[D]: Motor connector “E61” (viewed from harness side) 5. P/S control module 10. “IG1 SIG” fuse
1. Main fuse box 6. P/S motor 11. Motor circuit
DTC detecting condition Trouble area
DTC C1141:
Voltage between both motor drive circuit is more than 8.5
V or less than 0.2 V for 0.5 second continuously while
motor is not driven.
(1 driving cycle detection logic)
DTC C1142:
Measured motor drive current is more than 10 A as
compared with target motor drive current.
(1 driving cycle detection logic)
DTC C1143:
Measured motor drive current is more than 65 A.
(1 driving cycle detection logic)
DTC C1145:
Measured motor drive current is less than 2 A
continuously for more than 3 seconds even though target
motor drive current is more than 4 A.
or
Measured motor drive current is less than 0.8 A for total 1
second even though motor control duty is more than 90%
when target motor drive current is less than 8 A.
(1 driving cycle detection logic)• P/S motor circuit
• P/S motor
• Torque sensor
• P/S control module
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DTC Troubleshooting
DTC C1153: P/S Control Module Power Supply CircuitS6RW0D6304017
Wiring Diagram
DTC Detecting Condition and Trouble AreaStep Action Yes No
1Was “EPS System Check” performed?Go to Step 2. Go to “EPS System
Check”.
2DTC check
Is DTC C1153 and/or C1155 indicated, together?Go to applicable DTC
diag. flow.Go to Step 3.
3Power supply and ground circuit check
1) Check P/S control module power supply and ground
circuit referring to “P/S Control Module Power Supply
and Ground Circuit Check”.
Is it in good condition?Go to Step 4. Repair or replace
defective circuit.
4Motor circuit check
1) With ignition switch turned OFF, disconnect P/S control
module connector No.3 and P/S motor connector.
2) Check P/S control module connector and P/S motor
connector for proper connection.
3) If OK, check for open, short and/or high resistance in
motor circuit between P/S control module and P/S motor.
Refer to “Electrical Circuit Inspection Procedure in
Section 00”.
Are they in good condition?Go to Step 5. Repair motor circuit.
5P/S motor check
1) Check P/S motor referring to “P/S Motor and Its Circuit
Inspection”.
Is P/S motor in good condition?Substitute a known-
good P/S control
module and recheck.Replace the steering
gear case assembly and
recheck.
[A]
123
4567
8
9 11
10 12 13
141516
17 18 1920
1
2
[B]
LT GRN/
BLKE11-1E13-1 GRNGRN
WHT
5
3 6
8
9
7
4 12
12V
E13-2BLK
I6RW0C630009-01
[A]: P/S control module connector No.1 “E11” (viewed from harness side) 3. Junction block assembly 7. “IGN” fuse
[B]: P/S control module connector No.2 “E13” (viewed from harness side) 4. Main fuse 8. “P/S” fuse
1. Main fuse box 5. P/S control module 9. “IG1 SIG” fuse
2. Ignition switch 6. Individual circuit fuse box No.1
DTC detecting condition Trouble area
Power supply voltage of P/S control module is less than 9
V for 5 seconds continuously while engine speed is more
than 600 rpm.
(1 driving cycle detection logic)• P/S control module power supply circuit
• Battery
• Generator
• P/S control module
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NOTE
*: The voltage of this circuit may not be checked by voltmeter. If so, use oscilloscope.
Reference waveform No.1
Motor output signal 1(1), Motor output signal 2(2), with
engine idlingE11-20 REDReference sensor power supply
for torque sensorAbout 3.0 – 3.5 V• Ignition switch ON
• Check voltage between “E11-20” and
“E11-9” terminals
E12-1 BLK Motor output 1*0 – 1 V
↑↓
10 – 14 V
(“Reference
waveform No.1: ”,
“Reference
waveform No.2: ”
and “Reference
waveform No.3: ”)• Engine idling and steering wheel at
straight position
• Voltage between “E12-1” and vehicle
body ground
E12-2 RED Motor output 2*0 – 1 V
↑↓
10 – 14 V
(“Reference
waveform No.1: ”,
“Reference
waveform No.2: ”
and “Reference
waveform No.3: ”)• Engine idling and steering wheel at
straight position
• Voltage between “E12-2” and vehicle
body ground
E13-1 GRNMain power supply for internal
memory and P/S motor10 – 14 V —
E13-2 BLK Ground for P/S control module Below 0.3 V — Terminal Wire color Circuit Normal voltage Condition
Measurement
terminalCH1: “E12-1” to vehicle body ground
CH1: “E12-2” to vehicle body ground
Oscilloscope
settingCH1: 5 V/DIV, CH2: 5 V/DIV
TIME: 20 µs/DIV
Measurement
condition• Engine is idling and steering
wheel at straight position
I6RS0B630017-01
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Reference waveform No.2
Motor output signal 1(1), Motor output signal 2(2), with
engine idlingReference waveform No.3
Motor output signal 1(1), Motor output signal 2(2), with
engine idling
Measurement
terminalCH1: “E12-1” to vehicle body ground
CH1: “E12-2” to vehicle body ground
Oscilloscope
settingCH1: 5 V/DIV, CH2: 5 V/DIV
TIME: 20 µs/DIV
Measurement
condition• Engine is idling and steering
wheel is turned to left or right at
turning speed of 90° /sec
[A]: Steering wheel is turned left at turning speed of 90° /sec
[B]: Steering wheel is turned right at turning speed of 90° /sec
[C]: 12 V ON
[D]: GND ON
[E]: 1 duty cycle
I6RS0B630018-01
Measurement
terminalCH1: “E12-1” to vehicle body ground
CH1: “E12-2” to vehicle body ground
Oscilloscope
settingCH1: 5 V/DIV, CH2: 5 V/DIV
TIME: 20 µs/DIV
Measurement
condition• Engine is idling and steering
wheel is kept fully turned to left or
right until it stops
[A]: Steering wheel is kept fully turned left unit it stops
[B]: Steering wheel is kept fully turned right unit it stops
[C]: 12 V ON
[D]: GND ON
I6RS0B630019-01
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3) Inspect for proper toe referring to “Front Wheel
Alignment Inspection and Adjustment in Section 2B”.
4) After confirming proper toe, tighten tie-rod end lock
nut to specified torque.
Tightening torque
Tie-rod end lock nut (a): 45 N·m (4.5 kgf-m, 32.5
lb-ft)
5) Tighten wheel bolts to specified torque and lower
hoist.
Tightening torque
Wheel bolt: 85 N·m (8.5 kgf-m, 61.5 lb-ft)
Tie-Rod End InspectionS6RW0D6306004
• Inspect for play in ball joint.
• Inspect for play in rack end ball joint.
In either case, if found defective, replace.
Steering Shaft Joint On-Vehicle InspectionS6RW0D6306005
Check shaft joint for wear, breakage and any other
damage and replace if any defect exists.
Steering Gear Case Assembly Removal and
Installation
S6RW0D6306006
Removal
CAUTION!
Be sure to set front wheels (tires) in straight
direction and remove ignition key from key
cylinder before performing the following
steps, otherwise, contact coil of air bag
system may get damaged.
1) Remove steering joint cover.
2) Make alignment marks (1) on pinion shaft (2) and
joint of steering lower shaft (3) for a guide during
reinstallation.
3) Loosen joint bolt (steering column side) (4) and
remove joint bolt (pinion shaft side) (5) and
disconnect steering lower shaft (3) from pinion shaft
(2).
4) Disconnect torque sensor connector and P/S motor
connector from steering gear case.
5) Remove front suspension frame referring to “Front
Suspension Frame, Stabilizer Bar and/or Bushing
Removal and Installation in Section 2B”, and then
remove steering gear case.
Installation
1) Install grommet (1) as shown in figure.
I3RM0A630030-01
I4RS0A630043-01
I4RS0B630012-01
2. Protrusion
5
2
1
5
34
3
I4RS0B630013-01
1
2
1
2
I5RW0A630018-02
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2) Install steering gear case to vehicle, and then install
front suspension frame referring to “Front
Suspension Frame, Stabilizer Bar and/or Bushing
Removal and Installation in Section 2B”.
3) Install steering gear case to suspension frame (3) as
follows.
a) Set member bracket (2) to steering gear case
(1).
b) Install all steering gear case mounting bolts by
hand.
c) Tighten steering mounting bolts in numerical
order and specified torque.
Tightening torque
Steering gear case mounting bolt (a): 70 N·m (
7.0 kgf-m, 51.0 lb-ft)
4) Connect torque sensor connector and P/S motor
connector to steering gear case.
5) Be sure that steering wheel and brake discs (right &
left) are all straight-ahead position and then insert
steering lower shaft (5) into steering pinion shaft (3)
with matching marks (4).
6) Tighten steering shaft joint lower bolt (1) and upper
bolt (2) to specified torque (tighten lower side first
and then tighten upper side).
Tightening torque
Steering lower shaft assembly upper joint bolt
(a): 25 N·m (2.5 kgf-m, 18.5 lb-ft)
Steering lower shaft assembly lower joint bolt
(b): 25 N·m (2.5 kgf-m, 18.5 lb-ft)
7) Install steering joint cover.Steering Rack Boot InspectionS6RW0D6306007
Hoist vehicle.
Inspect each boot for tear. A torn boot allows entry of
dust and water which can cause wear to steering rack
and pinion to produce noise as well as rust to result in
malfunction of steering system.
Even if boot tear is small, replace with new one.
Also, check each boot for dent. If there is a dent, keep
boot in most compressed state for some seconds to
correct dent.
Boots should be visually inspected for any damage, dent
and tear during every periodical inspection at specified
intervals and whenever vehicle is hoisted for any other
purpose.
Tie-Rod / Rack Boot Removal and InstallationS6RW0D6306008
Removal
1) Remove steering gear case assembly referring to
“Steering Gear Case Assembly Removal and
Installation”.
2) Remove member bracket from steering gear case
assembly.
3) For ease of adjustment after installation, make
marking (1) of tie-rod end lock nut position of tie-rod
thread.
4) Loosen tie-rod end lock nut and remove tie-rod end.
5) Remove boot band (2) and clip (1).
6) Remove boot from tie-rod.I7RW01632009-01
5
4 1, (b)
3
2, (a)
1, (b)5
I5RW0A630020-01
I2RH01630012-01
I4RS0A630044-01
IYSQ01630034-01