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DTC Detecting Condition and Trouble Area
DTC TroubleshootingDTC detecting condition Trouble area
DTC C1121:
Vehicle speed signal is 0 km/h even though engine speed
is more than 4000 rpm for more than 60 seconds
continuously (before elapse of 5 min from engine start)
or
Vehicle speed signal is 0 km/h even though engine speed
is more than 2500 rpm for more than 60 seconds
continuously (after elapse of 5 min for engine start).
(1 driving cycle detection logic but “EPS” warning light
does not light up)
DTC C1123:
Vehicle speed signal is 0 km/h with continuously more
than 3 driving cycles even though engine speed is more
than 4000 rpm for more than 30 seconds continuously
(before elapse of 5 min from engine start)
or
Vehicle speed signal is 0 km/h with continuously more
than 3 driving cycles even though engine speed is more
than 2500 rpm for more than 30 seconds continuously
(after elapse of 5 min for engine start).
(3 driving cycle detection logic)
DTC C1124:
Vehicle speed signal is less than 5 km/h for more than 5
seconds continuously with more than specified
deceleration speed (–20 m/s
2) from over 20 km/h.
(1 driving cycle detection logic but “EPS” warning light
does not light up)• Vehicle speed signal circuit
•BCM
•ECM
• TCM (A/T model)
• ABS control module (M/T model)
• P/S control module
• CAN communication line circuit
Step Action Yes No
1Was “EPS System Check” performed?Go to Step 2. Go to “EPS System
Check”.
2DTC check
1) DTC check for ECM referring to “DTC Check in Section
1A”.
Is there any DTC detected?Go to applicable DTC
diag. flow.Go to Step 3.
3Vehicle spec check
Is vehicle equipped with A/T?Go to Step 4 Go to Step 5
4DTC check
1) Check TCM for DTC referring to “DTC Check in Section
5A”.
Is there any DTC detected?Go to applicable DTC
diag. flow.Go to Step 6.
5DTC check
1) Check ABS control module and BCM for DTC referring
to “DTC Check in Section 4E” and “DTC Check in
Section 10B”.
Is there any DTC detected?Go to applicable DTC
diag. flow.Go to Step 6.
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DTC C1122: Engine Speed SignalS6RW0D6304015
Wiring Diagram6Vehicle speed signal circuit check
1) With ignition switch turned OFF, disconnect connectors
from BCM.
2) Check BCM connector for proper connection.
3) If OK, turn ON ignition switch, measure voltage between
“G04-15” or “G04-22” wire terminal of BCM connector
and body ground.
Is voltage 4 – 5 V?Go to Step 7. Go to Step 8.
7BCM voltage check
1) With ignition switch turned OFF, connect BCM
connector.
2) Check BCM for vehicle speed signal output referring to
“Inspection of P/S Control Module and Its Circuits”.
Is it in good condition?Replace P/S control
module.Replace BCM.
8Vehicle speed signal circuit check
1) Check that vehicle speed signal circuit is as follows.
• Insulation resistance of wire harness is infinity
between “Vehicle speed signal” terminal and other
terminal at P/S control module connector.
• Wiring harness resistance of “Vehicle speed signal”
circuit is less than 1Ω.
• Insulation resistance between “Vehicle speed signal”
circuit and vehicle body ground is infinity.
• Circuit voltage between “Vehicle speed signal” circuit
and ground circuit is 0 – 1 V with ignition switch turned
ON.
Is it in good condition?Replace P/S control
module.Repair or replace
defective circuit. Step Action Yes No
[A]
123
4567
8
9 11
10 12 13
141516
17 18 1920
1
2
[B]
BRN LT GRN/
BLK
E11-1
E11-12
E13-1 GRN
GRN
WHT
6
37
9
10
8
4 12
12V
E13-2BLK12V5
11
[C]E01-44E01-4
I6RW0D630004-01
[A]: P/S control module connector No.1 “E11” (viewed from harness side) 3. Junction block assembly 8. “IGN” fuse
[B]: P/S control module connector No.2 “E13” (viewed from harness side) 4. Main fuse 9. “P/S” fuse
[C]: M15A engine with 4A/T equipped with slip control model (Hong Kong model) 5. ECM 10. “IG1 SIG” fuse
1. Main fuse box 6. P/S control module 11. Engine speed signal circuit
2. Ignition switch 7. Individual circuit fuse box No.1
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DTC Detecting Condition and Trouble Area
DTC TroubleshootingDTC detecting condition Trouble area
Engine speed signal is less than 220 rpm for more than
0.8 seconds.
or
Engine speed signal is less than 220 rpm for more than 20
seconds continuously even though vehicle speed signal is
more than 50 km/h.
(1 driving cycle detection logic)• Engine speed signal circuit
•ECM
• P/S control module
Step Action Yes No
1Was “EPS System Check” performed?Go to Step 2. Go to “EPS System
Check”.
2DTC check
1) Check ECM for DTC referring to “DTC Check in Section
1A”.
Is there any DTC(s) detected?Go to applicable DTC
diag. flow.Go to Step 3.
3Engine speed signal circuit check
1) With ignition switch turned OFF, disconnect P/S control
module connector.
2) Check P/S control module connector for proper
connection.
3) If OK, turn ON ignition switch, measure voltage between
“E11-12” wire terminal of P/S control module connector
and vehicle body ground.
Is voltage 10 – 14 V?Go to Step 4. Go to Step 5.
4ECM voltage check
1) With ignition switch turned OFF, connect P/S control
module and ECM connectors.
2) Check engine speed signal output referring to
“Inspection of ECM and Its Circuits in Section 1A”.
Is it in good condition?Substitute a known-
good P/S control
module and recheck.Substitute a known
good ECM and recheck.
5Engine speed signal circuit check
1) Disconnect ECM connector.
2) Check that engine speed signal circuit is as follows.
• Insulation resistance of wire harness is infinity
between “Engine speed signal circuit” terminal and
other terminal at P/S control module connector.
• Wiring harness resistance of “Engine speed signal
circuit” is less than 1Ω.
• Insulation resistance between “Engine speed signal
circuit” and vehicle body ground is infinity
• Circuit voltage between “Engine speed signal circuit”
and ground circuit is 0 – 1 V with ignition switch turned
ON.
Is it in good condition?Substitute a known
good ECM and recheck.Repair or replace
defective circuit.
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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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DTC Troubleshooting
DTC C1155: P/S Control Module Internal FailureS6RW0D6304018
Wiring Diagram
Refer to “DTC C1153: P/S Control Module Power Supply Circuit”.
DTC Detecting Condition and Trouble Area
DTC TroubleshootingStep Action Yes No
1Was “EPS System Check” performed?Go to Step 2. Go to “EPS System
Check”.
2Battery voltage check
1) Check circuit fuse for P/S control module.
2) If OK, measure voltage between positive (+) battery
terminal and vehicle body ground with engine running.
Is voltage 10 V or more?Go to Step 3. Check charging system
referring to “Generator
Test (Undercharged
Battery Check) in
Section 1J”.
3P/S control module power supply circuit check
Check power supply circuit and ground circuit for P/S control
module referring to “P/S Control Module Power Supply and
Ground Circuit Check”.
Is check result in good condition?Substitute a known-
good P/S control
module and recheck.Repair defective circuit.
DTC detecting condition Trouble area
Internal memory (EEPROM) is data error.
(In this case, “EPS” warning light does not light up)
or
Internal circuit is faulty.
or
Power supply voltage of P/S control module exceeded
17.5 V
(1 driving cycle detection logic)• Generator
• P/S control module
Step Action Yes No
1Was “EPS System Check” performed?Go to Step 2. Go to “EPS System
Check”.
2P/S control module power supply and ground circuit
check
Check power supply circuit and ground circuit for P/S control
module referring to “P/S Control Module Power Supply and
Ground Circuit Check”.
Is check result in good condition?Go to Step 3. Repair or replace
defective circuit.
3Battery voltage check
1) Check voltage between positive (+) battery terminal and
vehicle body ground with engine speed at 3000 rpm.
Is voltage 15.5 V or less?Replace P/S control
module.Check charging system
referring to “Generator
Test (Overcharged
Battery Check) in
Section 1J”.
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Terminal Wire color Circuit Normal voltage Condition
E11-1 LT GRN/BLKIgnition switch signal for P/S
control module10 – 14 V Ignition switch ON
E11-2 — — — —
E11-3 — — — —
E11-4 PPL Vehicle speed signal*0 – 1 V
↑↓
8 – 14 V
(“Reference
waveform No.7”
under “Inspection
of BCM and Its
Circuits in
Section 10B”)• Ignition switch ON
• Front left tire turned quickly with right
tire locked
E11-5 GRY “EPS” warning light0 V Ignition switch ON
0 – 14 V Engine running
E11-6 — — — —
E11-7 — — — —
E11-8 GRN9 V power supply for torque
sensorAbout 9 V• Ignition switch ON
• Voltage between “E11-8” and “E11-9”
terminals
E11-9 BLK Ground for torque sensors — —
E11-10 WHT Torque sensor signal (Sub)About 2.5 – 4.0 V• Steering wheel with left turn
• Out put voltage varies linearly
depending on steering force
About 2.5 V Steering wheel at free
About 1.0 – 2.5 V• Steering wheel with right turn
• Out put voltage varies linearly
depending on steering force
E11-11 BLUSerial communication circuit for
data link connector——
E11-12 BRN Engine speed signal*0 – 1 V
↑↓
8 – 14 V
(“Reference
waveform No.24
and No.25” under
“Inspection of
ECM and Its
Circuits in
Section 1A”)Engine idling
E11-13 — — — —
E11-14 RED/BLU P/S active signal (idle up signal)About 12 V Ignition switch ON
0 – 1 VEngine idling and turned steering wheel
to the right or left until it stops
E11-15 — — — —
E11-16 — — — —
E11-17 — — — —
E11-18 YEL Torque sensor signal (Main)About 1.0 – 2.5 V• Steering wheel with left turn
• Out put voltage varies linearly
depending on steering force
About 2.5 V Steering wheel at free
About 2.5 – 4.0 V• Steering wheel with right turn
• Out put voltage varies linearly
depending on steering force
E11-19 GRY Ground for shield wire — —
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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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8) Using ammeter (2), check that P/S motor current (1)
is as following table with idling engine. If check result
is not satisfactory, check P/S control module for
torque sensor signal and P/S motor output referring
to “Inspection of P/S Control Module and Its
Circuits”. If they are OK, replace steering gear case
assembly.
NOTE
When P/S motor is cold condition (that is,
armature coil of P/S motor is not heated),
motor current in the following table can be
measured
Motor current at hoisted vehicle (reference
value)
Specifications
Tightening Torque SpecificationsS6RW0D6307001
NOTE
The specified tightening torque is also described in the following.
“Steering Gear Case Assembly Components”
Reference:
For the tightening torque of fastener not specified in this section, refer to “Fasteners Information in Section 0A”. ConditionWhen
steering
wheel is left
at straight
position: [A]When steering
wheel is turned
left or right by
turning speed
with 90° /sec:
[B]When
steering
wheel is
kept fully
turned left
or right
until it
stops.: [C]
Motor
currentApprox. 0 A Approx. 0 – 5 AApprox.
45 – 60 A
3. P/S control module
1
32
E12-1
E12-2
[C][A]
[B] [B]
I7RW01632012-01
Fastening partTightening torque
Note
N⋅mkgf-mlb-ft
Tie-rod end nut 45 4.5 32.5 )
Tie-rod end lock nut 45 4.5 32.5 )
Wheel bolt 85 8.5 61.5 )
Steering gear case mounting bolt 70 7.0 51.0 )
Steering lower shaft assembly upper joint bolt 25 2.5 18.5 )
Steering lower shaft assembly lower joint bolt 25 2.5 18.5 )
Tie-rod 75 7.5 54.5 )
Earth cable bolt 4.0 0.4 2.8 )
Rack damper screw Tighten 25 N⋅m (2.5 kgf-m, 18.0 lb-ft) and
loosen 180° and then tighten 3.9 N⋅m (0.39
kgf-m, 3.0 lb-ft) and turn it back by 10° or
less by the specified procedure. )
Rotation torque of pinion 2.2 0.22 1.5 )
Steering rack damper lock nut 60 6.0 43.5 )