2007 SUZUKI SWIFT Service Workshop Manual

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Step 1: Customer Complaint Analysis
Record details of the problem (failure, co mplaint) and how it occurred as described by the customer. For this purpose,
use of such an inspection form will fac ilitate collecting information to the point required for proper analysis and
diagnosis. Check if the problem described in “Customer ques tionnaire” occurs actually in the vehicle if necessary.
(This step should be performed with the customer if possible.) Customer problem inspection form (Example)
NOTE
This form is a standard sample. It should be modified according to conditions characteristic of each
market.

I7RW01632004-02

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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

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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

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) 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

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Scan Tool DataS7RS0B6304006
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.

) C1143 P/S motor circuit current too
high Measured motor drive current is
more than 50 A.
• P/S motor circuit
• P/S motor
• P/S control module1 driving
cycle
) C1145 P/S motor circuit current too
low 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% while target motor
drive current is less than 8 A. 1 driving
cycle
) C1153 P/S control module power
supply circuit Power supply voltage of P/S
control module is less than 9 V for
5 seconds continuously. • P/S control module power
supply circuit
• Undercharged Battery
• P/S control module 1 driving
cycle
) C1155 P/S control module internal
failure Internal memory (EEPROM) is
data error.
• P/S control moduleNot
applicable
Internal circuit is faulty.
or
Power supply voltage of P/S
control module exceeded 17.5 V. • Overcharged Battery
• P/S control module
1 driving
cycle
DTC No. Detecting item
Detecting condition
(DTC will set when detecting) Trouble area MIL
Scan tool data
Vehicle conditionNormal condition
) Battery Voltage
Ignition switch ON 10 – 14 V
) TQS Power Supply 10 – 14 V
) TQS Main Torque Engine running at idle speed Steering wheel at fully turned to left –9.4 – 0 N
⋅m
Steering wheel at free 0 N⋅m
Steering wheel at fully turned to right 0 – 9.4 N ⋅m
) TQS Sub Torque Engine running at idle speed Steering wheel at fully turned to left –9.4 – 0 N
⋅m
Steering wheel at free 0 N⋅m
Steering wheel at fully turned to right 0 – 9.4 N ⋅m
) Assist Torque Engine running at idle speed Steering wheel at fully turned to left –9.4 – 0 N
⋅m
Steering wheel at free 0 N⋅m
Steering wheel at fully turned to right 0 – 9.4 N ⋅m
) Motor Control Engine running at idle speed Steering wheel at free
0 A
Steering wheel at fully turned to left or right *35 – 45 A
) Motor Monitor Engine running at idle speed Steering wheel at free
0 A
Steering wheel at fully turned to left or right *35 – 45 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 Volt Engine running at idle speed Steering wheel at free
0.8 – 1 V
Steering wheel at fully turned to right About 5 V
) Ignition switch Ignition switch ON ON

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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”.

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Serial Data Link Circuit CheckS7RS0B6304009
CAUTION!
Be sure to perform “EPS System Check” before starting “Troubleshooting”.

Wiring DiagramVehicle pulls to one side
during straight driving
Poor performance of torque sensor
Check torque sensor referring to “Torque
Sensor and Its Circuit Inspection”.
Steering gear case assembly faulty Replace.
Poor recovery after turns Poor performance of torque sensor Check torque sensor referring to “Torque
Sensor and Its Circuit Inspection”.
Steering column faulty Replace.
Abnormal noise P/S motor (built in steering gear case
assembly) malfunction Replace steering gear case assembly.
No idle up P/S control module faulty Check P/S control module referring to
“Inspection of P/S Control Module and Its
Circuits”.
Condition Possible cause Correction / Reference Item
MBLK
RED
E52-11 E51-1
E51-2PPL/WHT
[A ]
12
3
4 5 67
89
11
10
12 13
141516
17 18 19 2010 9 8 7654 3 21
16 15 14 13 12 11
26 25 24 2322 21 20 19 18 17
32 31 30 29 28 27
[C]
8
79
12V
[B ]
11
12
GRY
LT GRN
/BLK
E52-1
E52-5
E49-1
GRNGRNWHTBLK
WHY
G28-25G28-31
RED/BLK
10
3
4
4
5 6
4
4
1 2
4
E49-2BLK
I7RS0B630003-01
[A]: Connector “E52” (viewed from harness side) 3. Junction block assembly 8. P/S control module
[B]: Connector “E49” (viewed from harness side) 4. Fuse 9. T o ECM, BCM, Air bag SDM control module and ABS control
module assembly
[C]: Connector “G28” (viewed from harness side) 5. Comb ination meter 10. Individual circuit fuse box No.1
1. Main fuse box 6. “EPS” warning light 11. Serial data circuit
2. Ignition switch 7. Date link connector (DLC)

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TroubleshootingStep Action Yes No 1 Was “EPS System Check” performed? Go to Step 2. Go to “EPS System
Check”.
2 1) Make sure that SUZUKI scan tool is free from malfunction and that correct program card (software) for
P/S system is used.
2) Turn ignition switch to OFF position.
3) Check proper connection of SUZUKI scan tool to DLC.
Is connection in good condition? Go to Step 3. Connect SUZUKI scan
tool to DLC properly.
3 1) Check if communication is possible by making communication with other controllers (ECM, BCM, ABS
or SDM) or other vehicles.
Is it possible to communic ate with the other controllers? Go to Step 4. Repair open in common
section of “serial data
circuit” (“PPL/WHT” wire
circuit) used by all
controllers or short to
ground or power circuit
which has occurred
somewhere in serial
data circuit (“PPL/WHT”
wire circuit).
4 1) 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 5. Repair or replace
defective circuit.
5 1) With ignition switch turned OFF, disconnect “E52” connector from P/S control module and check for
terminal to P/S control module connector.
2) If connections are OK, check t hat “Serial data circuit” is
as following.
• Insulation resistance of “Serial data circuit” wire is infinity between its terminal and other terminals at P/S
control module connector.
• Wiring resistance of “Seria l data circuit” wire is less
than 1 Ω.
• Insulation resistance of “Serial data circuit” wire is infinity between its terminal and vehicle body ground.
Is circuit in good condition? Substitute a known-
good P/S control
module and recheck.
Repair or replace
defective circuit.