DT c1121 SUZUKI SWIFT 2005 2.G Service Workshop Manual

Page 867 of 1496

Downloaded from www.Manualslib.com manuals search engine Table of Contents 6- i
6
Section 6
CONTENTS
Steering
Precautions ................................................. 6-1
Precautions............................................................. 6-1
Precautions on Steering........................................ 6-1
Steering General Diagnosi s.................... 6A-1
Precautions........................................................... 6A-1
Precautions for Steering Diagnosis ..................... 6A-1
Diagnostic Information and Procedures ............ 6A-2 Steering Symptom Diagnosis .............................. 6A-2
Steering Wheel and Column ................... 6B-1
Precautions........................................................... 6B-1
Service Precautions of Steering Wheel and Column.............................................................. 6B-1
General Description ............................................. 6B-1 Steering Wheel and Column Construction .......... 6B-1
Diagnostic Information and Procedures ............ 6B-2 Checking Steering Column for Accident Damage ............................................................ 6B-2
Repair Instructions .............................................. 6B-3 Steering Wheel and Column Construction .......... 6B-3
Steering Wheel Removal and Installation ........... 6B-4
Contact Coil Cable Assembly Removal and Installation ......................................................... 6B-5
Centering Contact Coil Cable Assembly ............. 6B-6
Contact Coil Cable Assembly Inspection ............ 6B-6
Steering Angle Sensor Removal and Installation ......................................................... 6B-6
Steering Angle Sensor Inspection ....................... 6B-6
Steering Column Removal and Installation ......... 6B-7
Steering Column Inspecti on ................................ 6B-8
Ignition Switch Cylinder Assembly Removal and Installation (Non- Keyless Start Model)...... 6B-9
Steering Lock Assembly (Ignition Switch) Removal and Installation................................... 6B-9
Steering Lower Shaft Removal and Installation ....................................................... 6B-10
Specifications ..................................................... 6B-11
Tightening Torque Specifications ...................... 6B-11
Special Tools and Equipmen t ........................... 6B-11
Special Tool ...................................................... 6B-11
Power Assisted Steering System........... 6C-1
Precautions........................................................... 6C-1 Steering System Note .........................................6C-1
Precautions in Diagnosing Troubles ...................6C-1
General Description .............................................6C-2 P/S System Description ......................................6C-2
EPS Diagnosis General Descr iption ...................6C-3
On-Board Diagnostic System Description ...........6C-3
Schematic and Routing Diagram ........................6C-4 EPS System Wiring Circuit Diagram ...................6C-4
Diagnostic Information and Procedures ............6C-5 EPS System Check .............. ...............................6C-5
“EPS” Warning Light Check . ...............................6C-8
DTC Check..........................................................6C-8
DTC Clearance ...................................................6C-9
DTC Table ...........................................................6C-9
Scan Tool Data .................................................6C-11
Visual Inspection ...............................................6C-12
P/S System Symptom Diagnosis ......................6C-12
Serial Data Link Circuit Check ..........................6C-13
“EPS” Warning Light Do es Not Come ON with
Ignition Switch Turn ed ON before Engine
Starts ...............................................................6C-15
“EPS” Warning Light Remains ON Steady after Engine Starts ..........................................6C-16
DTC C1113: Steering Torque Sensor (Main and Sub) Circuit Correlation ............................6C-17
DTC C1114: Steering Torque Sensor Reference Power Supply Circuit .....................6C-19
DTC C1117: Steering Torque Sensor Failure Signal Circuit Low ...........................................6C-21
DTC C1118: Steering Torque Sensor Failure Signal Circuit High...........................................6C-22
DTC C1119: Steering Torque Sensor Power Supply Circuit ..................................................6C-24
DTC C1121 / C1123 / C1124: VSS Circuit
Failure .............................................................6C-26
DTC C1122: Engine Speed Signal....................6C-28
DTC C1141 / C1142 / C1143 / C1145: P/S Motor Circuit Failure ........................................6C-30
DTC C1153: P/S Control Module Power Supply Circuit Voltage Low .............................6C-32
DTC C1155: P/S Control Module Failure ..........6C-33
P/S Control Module Power Supply and Ground Circuit Check ......................................6C-34
Inspection of P/S Control Module and Its Circuits ............................................................6C-35

Page 892 of 1496

Downloaded from www.Manualslib.com manuals search engine 6C-10 Power Assisted Steering System:
) C1121 No vehicle speed signal
(60 seconds or more) 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). • Vehicle speed signal circuit
• Wheel speed sensor
•ECM
• P/S control module
• ABS control module
• CAN communication circuit
Not
applicable
) C1122 Engine speed signal 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.• Engine speed signal circuit
•ECM
• P/S control module
• Vehicle speed signal
1 driving
cycle
) C1123 No vehicle speed signal
(30 seconds or more) 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). • Vehicle speed signal circuit
• Wheel speed sensor
•ECM
• P/S control module
• ABS control module
• CAN communication circuit
3 driving
cycles
) C1124 Vehicle speed performance
(Impossible deceleration) 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. Not
applicable
) C1141 P/S motor circuit voltage Voltage between both motor drive
circuits is more than 8.5 V or less
than 0.2 V for 0.5 seconds
continuously while motor is not
drived.
• P/S motor circuit
• P/S motor
• P/S control module1 driving
cycle
) C1142 P/S motor circuit range /
performance Measured motor drive current is
more than 10 A as compared with
target motor drive current. 1 driving
cycle
DTC No. Detecting item
Detecting condition
(DTC will set when detecting) Trouble area MIL

Page 894 of 1496

Downloaded from www.Manualslib.com manuals search engine 6C-12 Power Assisted Steering System:
Scan Tool Data Definitions
Battery Voltage
This parameter indicates battery positive voltage.
TQS 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.
TQS Main Torque (Torque Sensor Main Torque, N ⋅m)
The torque sensor is installed to detect the steering force
and the steering directio n. It consists of two
potentiometers and the main torque sensor is one of
these.
TQS Sub Torque (Torque Sensor Sub Torque, N ⋅m)
The torque sensor is installed to detect the steering force
and the steering directio n. 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.
Assist 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. Motor Control (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 a ssist amount. This parameter
indicates that control value.
Motor Monitor (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 co mparing 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 diagnos is of the electric power
steering system.
Motor Volt (V)
This parameter indicates the voltage between motor
terminals.
Ignition switch (ON, OFF)
This parameter indicates the condition of the power
supply through the ignition switch.
Visual InspectionS7RS0B6304007
Visually check the following pats and system.
P/S System Symptom DiagnosisS7RS0B6304008
This section describes trouble diagnosis of the P/S system parts whose trouble is not indicated by the on-board
diagnostic system (self-diagnostic functi on). When no malfunction is indicated by the on-board diagnostic system
(self-diagnosis function) and those stee ring basic parts as described in “Steering Symptom Diagnosis in Section 6A”
are all in good condition, check the following power steer ing system parts which may be a possible cause for each
symptom of the steering. Inspection Item Referring section
Battery Level, leakage, color “Batte ry Description in Section 1J”
Connectors of electric wire
harness Disconnection friction “Intermittent and Poor
Connection Inspection in Section 00”
Fuses Burning “Cautions in Body Electric al System Servicing in Section 9A”
Parts Installation, damage
Other parts that can be checked visually
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 torque sensor Check torque sensor referring to “Torque
Sensor and Its Circuit Inspection”.
Poor performance of P/S motor Check motor referring to “P/S Motor and Its
Circuit Inspection”.
Steering gear case assembly faulty Replace.
Poor performance of vehicle speed
signal from ECM Check vehicle speed signal circuit referring to
“DTC C1121 / C1123 / C1124: VSS Circuit
Failure”.

Page 908 of 1496

Downloaded from www.Manualslib.com manuals search engine 6C-26 Power Assisted Steering System:
DTC C1121 / C1123 / C1124: VSS Circuit FailureS7RS0B6304017
DTC C1121: No Vehicle Speed Signal (60 Seconds or More)
DTC C1123: No Vehicle Speed Signal (30 Seconds or More)
DTC C1124: Vehicle Speed Performance (Impossible Deceleration)
Wiring Diagram
DTC Detecting Condition and Trouble Area
M
BRNRED/
BLU
BLK
RED
E52-14
E52-12
E23-4
E23-26
E23-25 E51-1
E51-2
[A ]
12
3
4 5 67
89
11
10
12 13
141516
17 18 19 20
5V
PPL
E52-4
8
5
12V
E49-2BLK
12V
12V
6REDRED/ BLKWHT
7WHTWHT/BLKWHTBLK BLK
111
2
[B ]
9
LT GRN
/BLKE52-1 E49-1
GRNGRNWHTBLK
WHY
10
3
4
4
4
4
1 2
12
I7RS0B630009-01
[A]: Connector “E52” (viewed from harness side)
4. Fuse9. ABS/ESP® control module
[B]: Connector “E49” (viewed from harness si de)5. ECM 10. Individual circuit fuse box No.1
1. Main fuse box 6. Left-front wheel speed sensor11. Vehicle speed signal circuit
2. Ignition switch 7. Right-front wheel speed sensor 12. Engine speed signal circuit
3. Junction block assembly 8. P/S control module
DTC 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 MIL 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 MIL does not light up) • Vehicle speed signal circuit
• Wheel speed sensor
•ECM
• P/S control module
• ABS/ESP®
control module
• CAN communication circuit

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Downloaded from www.Manualslib.com manuals search engine 6C-28 Power Assisted Steering System:
DTC C1122: Engine Speed SignalS7RS0B6304018
NOTE
DTC C1122 (engine speed signal failure) is indicated when ignition switch is at ON position and engine
is not running, but means there is nothing abnormal if indication changes to a normal one when
engine is started.

Wiring Diagram
Refer to “DTC C1121 / C1123 / C1124: VSS Circuit Failure”.
DTC Detecting Condition and Trouble Area DTC 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
• Vehicle speed signal circuit