Ecm SUZUKI SX4 2006 1.G Service Workshop Manual

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-10 Power Assisted Steering System:
)
C1121No 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
•BCM
•ECM
• TCM (A/T model)
• ABS control module (M/
T model)
• P/S control module
• CAN communication
line circuit1 driving
cycleDoes not
light up
)
C1122Engine speed signalEngine 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 module1 driving
cycle1 driving
cycle
)
C1123No 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
•BCM
•ECM
• TCM (A/T model)
• ABS control module (M/
T model)
• P/S control module
• CAN communication
line circuit3 driving
cycle3 driving
cycle
)
C1124Vehicle 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.1 driving
cycleDoes not
light up DTC No. Detecting itemDetecting condition
(DTC will set when detecting)Trouble area DTC“EPS”
warning
light

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 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-23
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.

Downloaded from www.Manualslib.com manuals search engine 6C-24 Power Assisted Steering System:
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.

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 Table of Contents 7- i
7
Section 7
CONTENTS
HVAC
Precautions ................................................. 7-1
Precautions............................................................. 7-1
Precautions on HVAC ........................................... 7-1
Heater and Ventilation............................. 7A-1
General Description ............................................. 7A-1
Heater and Ventilation Construction ................... 7A-1
Schematic and Routing Diagram ........................ 7A-2
Heater and Ventilation Wiring Circuit Diagram .... 7A-2
Component Location ........................................... 7A-2
Electronic Control System Components
Location ............................................................ 7A-2
Diagnostic Information and Procedures ............ 7A-3
Heater and Ventilation Symptom Diagnosis........ 7A-3
Repair Instructions .............................................. 7A-4
HVAC Unit Components ..................................... 7A-4
HVAC Unit Removal and Installation (Non-A/
C) ...................................................................... 7A-4
Blower Motor Removal and Installation............... 7A-4
Blower Motor Inspection ..................................... 7A-4
Blower Motor Resistor Removal and
Installation ......................................................... 7A-5
Blower Motor Resistor Inspection ....................... 7A-5
Blower Motor Relay Inspection ........................... 7A-6
HVAC Control Unit Components ......................... 7A-6
HVAC Control Unit Removal and Installation ...... 7A-7
Blower Speed Selector Inspection ...................... 7A-9
Air Intake Selector Inspection ............................. 7A-9
Air Intake Control Actuator Removal and
Installation ......................................................... 7A-9
Air Intake Control Actuator Inspection .............. 7A-10
Center Ventilation Louver Removal and
Installation ....................................................... 7A-11
Side Ventilation Louver Removal and
Installation ....................................................... 7A-11
Rear Duct Removal and Installation (If
Equipped)........................................................ 7A-12
HVAC Air Filter Removal and Installation (If
Equipped)........................................................ 7A-12
HVAC Air Filter Inspection (If Equipped) ........... 7A-12
Air Conditioning System......................... 7B-1
Manual Type ............................................................ 7B-1
Precautions........................................................... 7B-1A/C System Caution ............................................ 7B-1
Precautions on Servicing A/C System ................ 7B-1
General Description .............................................7B-2
Sub-Cool A/C System Description ...................... 7B-2
Manual A/C Electronic Input Output Table .......... 7B-3
A/C Operation Description at ECM ..................... 7B-3
Schematic and Routing Diagram ........................7B-4
A/C System Air Flow Diagram............................. 7B-4
A/C System Wiring Diagram ............................... 7B-5
Component Location ...........................................7B-6
A/C System Major Components Location ........... 7B-6
Electronic Control System Components
Location............................................................. 7B-7
Diagnostic Information and Procedures ............7B-8
A/C System Performance Inspection .................. 7B-8
Trouble Diagnosis for Abnormal Pressure ........ 7B-11
A/C System Inspection at ECM ......................... 7B-12
A/C System Symptom Diagnosis ...................... 7B-13
Abnormal Noise Symptom Diagnosis of A/C
System ............................................................ 7B-15
Repair Instructions ............................................7B-17
Operation Procedure for Refrigerant Charge .... 7B-17
Condenser Cooling Fan Removal and
Installation ....................................................... 7B-22
Condenser Cooling Fan Inspection ................... 7B-23
Condenser Assembly On-Vehicle Inspection .... 7B-23
Condenser Assembly Removal and
Installation ....................................................... 7B-23
Desiccant Removal and Installation .................. 7B-24
HVAC Unit Components ................................... 7B-25
HVAC Unit Removal and Installation ................ 7B-26
Evaporator Inspection ....................................... 7B-27
Evaporator Temperature Sensor Removal
and Installation ................................................ 7B-27
Evaporator Temperature Sensor Inspection ..... 7B-28
Expansion Valve Removal and Installation ....... 7B-28
Expansion Valve Inspection .............................. 7B-28
A/C Refrigerant Pressure Sensor and Its
Circuit Inspection............................................. 7B-29
A/C Refrigerant Pressure Sensor Removal
and Installation ................................................ 7B-29
A/C Switch Inspection ....................................... 7B-29
A/C System Relay Inspection............................ 7B-30
Compressor Drive Belt Inspection and
Adjustment ...................................................... 7B-30