2008 SUZUKI SWIFT module can

Downloaded from www.Manualslib.com manuals search engine 5A-74 Automatic Transmission/Transaxle:
DTC P1778: TCM Lost Communication with BCM (Reception Error)S7RS0B5104041
Wiring Diagram
Refer to “DTC P1774: CAN Communication Bus Off”.
DTC Detecting Condition and Trouble Area
DTC Confirmation Procedure
1) Connect scan tool to DLC with ignition switch OFF.
2) Clear DTC.
3) Start engine and run it for 1 min. or more.
4) Check DTC.
DTC Troubleshooting
NOTE
Upon completion of inspection and repair work, perform “DTC Confirmation Procedure:” “DTC
Confirmation Procedure” and confirm that the trouble has been corrected.

DTC detecting condition Trouble area
Reception error of communication data fo r BCM is detected more than specified
time continuously. •ECM
•TCM
•BCM
• ABS control module
• CAN circuit
Step
Action YesNo
1 Was “A/T System Check” performed? Go to Step 2.Go to “A/T System
Check”.
2 Control module connector check
1) Check connection of connectors of all control modules
communicating by means by means of CAN.
2) Recheck DTC.
Is there DTC P1778? Go to Step 3.
Intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection
Inspection in Section
00”.
3 DTC check in BCM (bus off)
1) Check BCM for DTC referring to “DTC Check in Section
10B”.
Is there DTC U1073? Go to “DTC U1073 (No.
1073): Control Module
Communication Bus Off
in Section 10B”.
Go to Step 4.
4 DTC check in ABS control module
1) Check ABS control module for DTC referring to “DTC
Check in Section 4E”.
Is there DTC U1100? Go to “DTC U1100: Lost
Communication with
ECM (Reception Error)
in Section 4E”.
Go to Step 5.
5 DTC check in ECM
1) Check ECM for DTC referring to “DTC Check in Section
1A”.
Is there DTC P1678? Check BCM power and
ground circuit. If circuit
is OK, substitute a
known-good BCM and
recheck.Go to Step 6.
6 CAN communication circuit check
1) Turn ignition switch to OFF position.
2) Disconnect connectors of all control modules
communicating by means of CAN.
3) Check CAN communication circuit between control modules for open, short and high resistance.
Is each CAN communication circuit in good condition? Check TCM power and
ground circuit. If circuit
is OK, substitute a
known-good TCM and
recheck.
Repair circuit.

Downloaded from www.Manualslib.com manuals search engine 5A-82 Automatic Transmission/Transaxle:
Inspection of TCM and Its CircuitsS7RS0B5104045
TCM and its circuits can be checked at TCM wiring connec tors by measuring voltage, pulse signal and resistance.
CAUTION!
TCM cannot be checked by itself, it is strictly prohibited to connect voltmeter or ohmmeter to TCM with
connector disconnected from it.

1) Remove TCM (1) from vehicle referring to “Transmission Control Module (TCM) Removal and Installation”.
2) Connect TCM connectors (2) to TCM.
3) Check voltage and/or pulse signal at each terminal of connectors connected using voltmeter (3) and oscilloscope
(4).
NOTE
• As each terminal voltage is affected by battery voltag e, confirm that it is 11 V or more when ignition
switch is ON.
• Voltage with asterisk(*) cannot be measured by voltmeter because it is pulse signal. Check it with oscilloscope if necessary.

Terminal arrangement of TCM coupler (Viewed from harness side)
5. Body ground
3
5 4
12
I6RS0C510009-01
65
16 15 14 13 12 11 43
24 23 2122 10 9 8 721
1920 18 17
C34
17 16
26 25
15 14
65 3
42
13 12
23 2224 11 10 9
21 20 19 87
18
1
C35
I4RS0A510022-01

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

Downloaded from www.Manualslib.com manuals search engine 6B-1 Steering Wheel and Column:
Steeri ng
Steering Wheel and Column
Precautions
Service Precautions of Steering Wheel and
Column
S7RS0B6200001
For service precautions, refer to “Precautions on Service
and Diagnosis of Air Bag System in Section 8B”.
Service and Diagnosis
For diagnosis and servicing, refer to “Precautions on
Service and Diagnosis of Air Bag System in Section 8B”.
Disabling Air Bag System
For disabling air bag system, refer to “Disabling Air Bag
System in Section 8B”. Enabling Air Bag System
For enabling air bag system, refer to “Enabling Air Bag
System in Section 8B”.
Handling and Storage
For handling and storage, refer to “Precautions on
Handling and Storage of Air Bag System Components in
Section 8B”.
Disposal
For disposal, refer to “Prec
autions on Disposal of Air
Bag and Seat Belt Pretensioner in Section 8B”.
General Description
Steering Wheel and Column ConstructionS7RS0B6201001
This double tube type steering column has the following three important features in addition to the steering function:
• The column is energy absorbing, desig ned to compress in a front-end collision.
• The ignition switch and lock are mounted conveniently on this column.
• With the column mounted lock, the ignition and steering op erations can be locked to inhibit theft of the vehicle.
To insure the energy absorbing action, it is important th at only the specified screws, bolts and nuts be used as
designated, and that they are tightened to the specified torque. When the column assembly is removed from the
vehicle, special care must be taken in handling it. Use of a steering wheel puller or a sharp blow on the end of the
steering shaft, leaning on the assembly, or dropping the a ssembly could shear the plastic shear pins which maintain
column length and position.
The driver air bag (inflator) module is one of the supplemental restraint (air bag) system components and is mounted
to the center of the steering wheel. During certain frontal crashes, the air bag system supplements the restraint of the
driver’s and passenger’s seat belts by deploying the air b ags. The air bag (inflator) module should be handled with
care to prevent accidental deployment. When servicing, be sure to observe “Precautions on Service and Diagnosis of
Air Bag System in Section 8B”.

Downloaded from www.Manualslib.com manuals search engine Power Assisted Steering System: 6C-1
Steeri ng
Power Assisted Steering System
Precautions
Steering System NoteS7RS0B6300001
NOTE
All steering gear fasteners are important attaching parts in that they could affect the performance of
vital parts and systems, and/or could result in major repair expense. They must be replaced with one of
the same part number or with an equivalent part if replacement becomes necessary. Do not use a
replacement part of lesser quality or substitute design. Torque values must be used as specified
during reassembly to assure proper retention of these parts.

Precautions in Diagnosing TroublesS7RS0B6300002
• Take a note of DTC indicated on the SUZUKI scan tool.
• Before inspection, be sure to read “Pre cautions for Electrical Circuit Service in Section 00” and understand what is
written there.
• DTC C1122 (engine speed signal failure) is indicated when ignition switch is at ON position and engine is not
running, but it means there is nothing abnormal if indica tion changes to a normal one when engine is started.
• As DTC is stored in memory of the P/S control module, be sure to clear memory after repair by performing the
procedure described in “DTC Clearance”.

Downloaded from www.Manualslib.com manuals search engine 6C-8 Power Assisted Steering System:
Step 2: DTC Check, Record and Clearance
First, check DTC, referring to “DTC Check”. If DTC is
indicated, print it or write them down and then clear them
by referring to “DTC Clearance”. DTC indicates
malfunction that occurred in the system but does not
indicate whether it exists now or it occurred in the past
and the normal condition has been restored now. To
check which case applies, check the symptom in
question according to Step 5 and recheck DTC
according to Step 6 and 7.
Attempt to diagnose a trouble based on DTC in this step
only or failure to clear the DTC in this step will lead to
incorrect diagnosis, trouble diagnosis of a normal circuit
or difficulty in troubleshooting.
Step 3 and 4: Visual Inspection
As a preliminary step, be sure to perform visual check of
the items that support proper function of the P/S system
referring to “Visual Inspection”.
Step 5: Trouble Symptom Confirmation
Based on information obtained in “Step 1: Customer
Complaint Analysis: ” and “S tep 2: DTC Check, Record
and Clearance: ”, confirm trouble symptoms. Also,
reconfirm trouble symptom by performing test drive and
turning steering wheel fully to right and left at stopped
vehicle.
Step 6 and 7: Rechecking and Record of DTC
Refer to “DTC Check” for checking procedure.
Step 8: Steering Symptom Diagnosis and P/S
System Symptom Diagnosis
Perform basic steering system check according to
“Steering Symptom Diagnosis in Section 6A” first. When
the end of the flow has been reached, check the parts of
the system suspected as a possible cause referring to
“P/S System Symptom Diagnosis” and based on
symptoms appearing on the vehicle (symptoms obtained
through steps of customer complaint analysis, trouble
symptom confirmation and/or basic P/S system check)
and repair or replace faulty parts, if any.
Step 9: Troubleshooting for DTC (See each DTC
Diag. Flow)
Based on the DTC indicated in Step 6 or 7 and referring
to the applicable DTC diag. flow, locate the cause of the
trouble, namely in a sensor, switch, wire harness,
connector, actuator, P/S control module or other part and
repair or replace faulty parts.
Step 10: Intermittent Problems Check
Check parts where an intermittent trouble is easy to
occur (e.g., wire harness, connector, etc.), referring to
“Intermittent and Poor Connection Inspection in Section
00” and related circuit of DTC recorded in Step 2. Step 11: Final Confirmation Test
Confirm that the problem symptom has gone and the P/
S system is free from any abnormal conditions. If what
has been repaired is related to the DTC, clear the DTC
once, perform DTC confirmation procedure and confirm
that no DTC is indicated.
“EPS” Warning Light CheckS7RS0B6304002
1) Turn ignition switch to ON position (without engine
running) and chec k if the “EPS” warning light (1)
lights up. If the light dose not light up, go to ““EPS”
Warning Light Does Not Come ON with Ignition
Switch Turned ON before Engine Starts” of the
diagnostic flows.
2) Start engine and check if the “EPS” warning light turns OFF. If light remains ON and no DTC is stored
in P/S control module, go to ““EPS” Warning Light
Remains ON Steady after Engine Starts” for
troubleshooting.
DTC CheckS7RS0B6304003
1) Turn ignition switch to OFF position.
2) Connect SUZUKI scan tool to data link connector (DLC) (1) located on underside of instrument panel
at driver’s seat side.
Special tool
(A): SUZUKI scan tool
1
I6RS0C630002-01
(A)
1
I4RS0B450003-01

Downloaded from www.Manualslib.com manuals search engine Power Assisted Steering System: 6C-9
3) Start engine.
4) Read DTC according to the instructions displayed on
SUZUKI scan tool. For further details, refer to
operator’s manual for SUZUKI scan tool.
NOTE
• If communication between SUZUKI scan tool and the vehicle can not be
established, perform “Serial Data Link
Circuit Check”.
• DTC C1122 (engine speed signal failure) is indicated when ignition switch is at ON
position and engine is not running, but it
means there is nothing abnormal if
indication changes to a normal one when
engine is started.

5) After completing the check, turn ignition switch to
OFF position and disconnect SUZUKI scan tool from
DLC.
DTC ClearanceS7RS0B6304004
1) Turn ignition switch to OFF position.
2) Connect SUZUKI scan tool to data link connector (DLC) (1) located on underside of instrument panel
at driver’s seat side.
Special tool
(A): SUZUKI scan tool
3) Turn ignition switch to ON position.
4) Erase DTC according to the instructions displayed on SUZUKI scan tool. For further details, refer to
operator’s manual for SUZUKI scan tool.
5) After completing the clearance, turn ignition switch to OFF position and disconnect SUZUKI scan tool from
DLC.
DTC TableS7RS0B6304005
CAUTION!
Be sure to perform the “EPS Syst em Check” before starting troubleshooting corresponding to each
DTC.

(A)
1
I4RS0B450003-01
DTC No. Detecting item Detecting condition
(DTC will set when detecting) Trouble area MIL
No
CODES Normal — — —
) C1113 Steering torque sensor (Main
and Sub) circuit correlation Voltage difference between torque
sensor main signal and sub signal
is more than 0.6 V for 1 second
continuously. • Torque sensor signal circuit
• Torque sensor
• P/S control module
1 driving
cycle
) C1114 Steering torque sensor
reference power supply
circuit Circuit voltage of torque sensor 5
V reference power supply voltage
is more than 5.7 V or less than 4.3
V for 1 second continuously. • Torque sensor circuit
• Torque sensor
• P/S control module
1 driving
cycle
) C1117 Steering torque sensor
failure signal circuit low Torque sensor internal failure
signal circuit voltage is less than
1.7 V when ignition switch turned
ON.
• Torque sensor signal circuit
• Torque sensor
• P/S control module1 driving
cycle
) C1118 Steering torque sensor
failure signal circuit high Torque sensor internal failure
signal circuit voltage is more than
3.7 V for 1 second continuously. 1 driving
cycle
) C1119 Steering torque sensor
power supply circuit Circuit voltage of torque sensor
main power supply
is less than
7.5 V for 1 second continuously. • Torque sensor circuit
• Torque sensor
• P/S control module
1 driving
cycle

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