2006 SUZUKI SX4 wheel torque

Downloaded from www.Manualslib.com manuals search engine 6C-2 Power Assisted Steering System:
General Description
P/S System DescriptionS6RW0D6301001
This electronic power steering (EPS) system consists of a power steering (P/S) control module (3), a torque sensor
(4), a P/S motor (5). In this system, the P/S control module determines the level and direction of the assist force for the
steering wheel (1) according to the signal from the torque sensor and the vehicle speed signal from BCM (9). The P/S
control module runs the motor so as to assist the operation of the steering wheel.
The P/S control module diagnoses troubles which may occur in the area including the following components when the
ignition switch is ON and the engine is running. When the P/S control module detects any malfunction, it stops the
motor operation.
• Torque sensor
• Vehicle speed signal circuit
• Engine speed signal circuit
• P/S Motor
• P/S control module.
1
32
4
6
7
5
8
9
I7RW01632001-01
2. Steering column 7. Battery
6. Steering gear case assembly 8. ECM

Downloaded from www.Manualslib.com manuals search engine 6C-4 Power Assisted Steering System:
Schematic and Routing Diagram
EPS System Wiring Circuit DiagramS6RW0D6302001
[A]
123
45
3 21
4
567
8
9 11
10 12 13
141516
17 18 19201
2
[B]
1
2
[C] [D]
10 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
[F][E]
12
BRN RED/
BLU GRY LT GRN/
BLK
BLK
RED
WHT GRN
BLK
E11-1
E11-5
E11-14
E11-12
[J]:E01-44E01-4
[J]:E01-27E01-26
E12-1
E12-2
E11-10E11-8
E11-9
E11-19
E13-1 GRN
GRY
GRN
WHT
G241-25G241-31
RED/BLK
11
12
1314 3 18
20
21
7 19
4 12
22
12V
E13-2BLK
9V
REDE11-20
12V
12V
E61-2
E61-1
610
55
5V
8
E11-115V
PPL
E11-4
9
23
+BB
BLU/
WHTE04-9
1524YELE11-18E31-5
E31-2
E31-39V
3V
E31-4
E31-1IG11617
C07-25
[H]
[G]
G04-15
[I]:G04-22
25L313-3
[I]
I6RW0D630001-01
[A]: P/S control module connector No.1 “E11” (viewed from harness side) 3. Junction block assembly 15. BCM
[B]: P/S control module connector No.2 “E13” (viewed from harness side) 4. Main fuse 16. Output shaft speed sensor
[C]: P/S control module connector No.3 “E12” (viewed from harness side) 5. Front (left/right) wheel speed sensor 17. TCM
[D]: Combination meter connector “G241” (viewed from harness side) 6. ABS control module 18. Individual circuit fuse box No.1
[E]: Torque sensor connector “E31” (viewed from harness side) 7. Combination meter 19. “IGN” fuse
[F]: Motor connector “E61” (viewed from harness side) 8. “EPS” warning light 20. “P/S” fuse
[G]: M/T model 9. Data link connector (DLC) 21. “IG1 SIG” fuse
[H]: A/T model 10. ECM 22. “MTR” fuse
[I]: Junction block without BCM model (Taiwan model) 11. P/S control module 23. To ABS control module
[J]: M15A engine with 4A/T equipped with slip control model (Hong Kong
model)12. P/S motor 24. To HVAC control module
1. Main fuse box 13. Shield 25. To SDM
2. Ignition switch 14. Torque sensor (built into steering gear case)

Downloaded from www.Manualslib.com manuals search engine 6C-12 Power Assisted Steering System:
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

Downloaded from www.Manualslib.com manuals search engine Power Assisted Steering System: 6C-13
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”.

Downloaded from www.Manualslib.com manuals search engine 6C-22 Power Assisted Steering System:
DTC C1121 / C1123 / C1124: Vehicle Speed Signal Circuit FailureS6RW0D6304014
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 Diagram5Torque sensor power supply circuit check
1) Check that torque sensor power supply circuit is as
follows.
• Insulation resistance of wire harness is infinity
between “Torque sensor power supply circuit” terminal
and each other terminal at torque sensor connector.
• Wiring harness resistance of “Torque sensor power
supply circuit” is less than 1 Ω.
• Insulation between “Torque sensor power supply
circuit” and vehicle body ground is infinity.
Is circuit 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 RED/
BLU LT GRN/
BLK
E11-1
E11-14
E11-12
E13-1 GRN
GRN
WHT
8
3 10
12
13
11
4 1
2
12V
E13-2BLK
12V
12V
9 5
77
E11-11
G04-15
[E]G04-22
5V
PPL
E11-4
BLU/
WHTE04-9
6
14
IG11615
C07-25
[D][C]
[F]E01-44E01-4
[F]E01-27E01-26
I6RW0D630003-01
[A]: P/S control module connector No.1 “E11” (viewed from harness side) 3. Junction block assembly 11. “IGN” fuse
[B]: P/S control module connector No.2 “E13” (viewed from harness side) 4. Main fuse 12. “P/S” fuse
[C]: M/T model 5. ECM 13. “IG1 SIG” fuse
[D]: A/T model 6. BCM 14. Vehicle speed signal
[E]: Junction block without BCM model (Taiwan model) 7. Front left/right wheel speed sensor 15. TCM
[F]: M15A engine with 4A/T equipped with slip control model (Hong Kong model) 8. P/S control module 16. Output shaft speed sensor
1. Main fuse box 9. ABS control module
2. Ignition switch 10. Individual circuit fuse box No.1

Downloaded from www.Manualslib.com manuals search engine Power Assisted Steering System: 6C-31
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 — —

Downloaded from www.Manualslib.com manuals search engine 6C-32 Power Assisted Steering System:
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

Downloaded from www.Manualslib.com manuals search engine 6C-34 Power Assisted Steering System:
Steering Wheel Play CheckS6RW0D6304021
• Check steering wheel for looseness or rattle by
moving it in its shaft direction and lateral direction.
If found defective, repair or replace.
• Check steering wheel for play, holding vehicle in
straight forward condition on the ground with engine
stopped.
If steering wheel play is not within specification,
inspect as follows and replace if found defective.
– Tie-rod end ball stud for wear (Ball stud should
move when more than 0.2 N⋅m (2 kg-cm, 0.44 lb-ft)
torque is applied.)
– Lower ball joint for wear
– Steering shaft joint for wear
– Steering pinion or rack gear for wear or breakage
– Each part for looseness
Steering wheel play
“a”
: 0 – 30 mm (0 – 1.18 in.)
Steering Force CheckS6RW0D6304022
1) Place vehicle on level road and set steering wheel at
straight-ahead position.
2) Check if tire inflation pressure is as specified
referring to the tire placard.
3) Remove driver air bag (inflator) module referring to
“Driver Air Bag (Inflator) Module Removal and
Installation in Section 8B”.
4) Start engine.
5) With engine idling, measure steering force by turning
torque wrench.
Steering force
: Less than 6.4 N⋅m (0.64 kgf-m, 4.6 lb-ft)
6) Install driver air bag (inflator) module referring to
“Driver Air Bag (Inflator) Module Removal and
Installation in Section 8B”.
I3RM0A630021-01
I3RM0A630022-01