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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
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”.
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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.
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“EPS” Warning Light Remains ON Steady after Engine StartsS7RS0B6304011
Wiring Diagram
Refer to ““EPS” Warning Light Does Not Come ON with Ignition Switch Turned ON before Engine Starts”.
Circuit Description
Operation (ON/OFF) of “EPS” warning light is controlled by P/S c ontrol module through combination meter.
If the P/S system is in good condition, P/S control module tu rns “EPS” warning light ON at the ignition switch ON, and
then turns it OFF at the engine start. If an abnormality in the system is detected, “EPS” warning light is turned ON
continuously by P/S control module. If P/S control module is disconnected, “EPS” warning light is not turned ON.
Troubleshooting 4 1) Check for proper connection to the combination meter at
“G28-25” terminal and P/S control module at “E52-5”
terminal.
2) Measure resistance between the combination meter at “G28-25” terminal and the P/S control module at “E52-5”
terminal.
Is it infinite (
∞)? “EPS warning light
circuit” is open.
Go to Step 5.
5 1) Connect combination meter connector (“G28”) with ignition switch turned OFF.
2) Check for voltage between “E52-5” (“GRY” wire) terminal and body ground with ignition switch ON.
Is it 10 – 14 V? Replace the P/S control
module.
Replace the
combination meter.
Step
Action YesNo
Step Action YesNo
1 1) Check DTC referring to “DTC Check”.
Is there any DTC(s) (NO CODES on SUZUKI scan tool)? Go to applicable DTC
diag. flow.
Go to Step 2.
2 1) With ignition switch OFF, disconnect P/S control module connector (“E52”).
2) Check for proper connection to the P/S control module at “E52-5” terminal.
3) If OK, then turn ignition switch to ON position.
Does “EPS” warning light turn on? Go to Step 3.
Replace the P/S control
module.
3 1) With ignition switch turned OFF, remove combination meter and its connector.
2) Check for proper terminal connection to combination meter connector.
3) If connections are OK, ch eck that “EPS warning light
circuit” is as following.
• Insulation resistance of “EPS warning light circuit” wire is infinity between its terminal and each terminal
at combination meter connector.
• Wiring resistance of “EPS wa rning light circuit” wire is
less than 1 Ω.
• Insulation resistance of “EPS warning light circuit” wire is infinity between its terminal and vehicle body
ground.
Is circuit in good condition? Replace the
combination meter.
Repair EPS warning
light circuit.
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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Inspection of P/S Control Module and Its CircuitsS7RS0B6304023
The P/S control module (1) and its circuits can be checked at the P/S control module wiring couplers (2) by measuring
voltage and resistance.
CAUTION!
P/S control module cannot be checked by itself. It is strictly prohibited to connect voltmeter or
ohmmeter to the P/S control module with connectors disconnected from the P/S control module.
5 P/S control module ground circuit check
1) Connect connectors to P/S control module.
2) Start engine.
3) Measure voltage between “E49-2” terminals of P/S
control module connector and body ground when
steering wheel fully turned to left or right.
Is voltage 0.3 V or less? P/S Control Module
Power Supply and
Ground Circuit is in
good condition.
“BLK” wire is open or
high resistance circuit.
Step Action Yes No
[A]
12
3
4 5 67
89
11
10
12 13
141516
17 18 19 20
[B]
[C]
12
1
1 2
2
I6RS0C630016-03
[A]: Connector “E52” (viewed from harness side) [C]: Connector “E49” (viewed from harness side)
[B]: Connector “E51” (viewed from harness side)
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Installation1) Mount steering gear case (1) to front suspension frame (2) and tighten gear case mounting No.1 bolts
(3), No.2 bolts (4) and No .3 bolts (5) to specified
torque.
Tightening torque
Steering gear case mounting No.1 bolt (a): 55
N·m (5.5 kgf-m, 40.0 lb-ft)
Steering gear case mounting No.2 bolt (b): 55
N·m (5.5 kgf-m, 40.0 lb-ft)
Steering gear case mounting No.3 bolt (c): 40
N·m (4.0 kgf-m, 29.0 lb-ft)
2) Install earth cable (6) as shown in figure. Tightening torque
Earth cable bolt (d): 4.5 N·m (0.45 kgf-m, 3.5 lb-
ft)
3) Install grommet (1) whose projection (2) orients vehicle forward.
4) Install front suspension frame with steering gear case assembly referring to “Front Suspension
Frame, Stabilizer Bar and/or Bushings Removal and
Installation in Section 2B”.Steering Rack Boot InspectionS7RS0B6306007
Hoist vehicle.
Inspect each boot for tear. A torn boot allows entry of
dust and water which can cause wear to steering rack
and pinion to produce noise as well as rust to result in
malfunction of steering system.
Even if boot tear is small, replace with new one.
Also, check each boot for dent. If there is a dent, keep
boot in most compressed st ate for some seconds to
correct dent.
Boots should be visually inspected for any damage, dent
and tear during every periodical inspection at specified
intervals and whenever vehicle is hoisted for any other
purpose.
Tie-Rod / Rack Boot Removal and InstallationS7RS0B6306008
Removal
1) Remove steering gear case assembly referring to
“Steering Gear Case Assembly Removal and
Installation”.
2) For ease of adjustment after installation, make marking (1) of tie-rod end lock nut position of tie-rod
thread.
3) Loosen tie-rod end lock nut and remove tie-rod end.
4) Remove boot band (2) and clip (1).
5) Remove boot from tie-rod.
F: Vehicle forward
1 2
3, (a) 4, (b)
6, (d)
5, (c)
I6RS0C630019-02
12
F
I6RS0C630020-01
I2RH01630012-01
I4RS0A630044-01
IYSQ01630034-01
Downloaded from www.Manualslib.com manuals search engine 6C-46 Power Assisted Steering System:
P/S Control Module Removal and InstallationS7RS0B6306011
Removal1) Disconnect negative cable at battery.
2) Remove console box.
3) Disconnect connectors (1) from P/S control module (2).
4) Disconnect connector from yaw rate / G sensor
(ESP ® model).
5) Remove P/S control module (2) with bracket (3) from floor panel.
6) Separate P/S control module and bracket.
Installation
Reverse removal procedure for installation noting the
following.
• Tighten each screw to the specified torque. Tightening torque
P/S control module bracket screw (ABS model)
(a): 9 N·m (0.9 kgf-m, 6.5 lb-ft)
P/S control module bracket screw (ESP ® model)
(a): 7 N·m (0.7 kgf-m, 5.0 lb-ft)
P/S control module mounting screw (b): 5 N·m (
0.5 kgf-m, 3.7 lb-ft)
Torque Sensor and Its Circuit InspectionS7RS0B6306012
1) Remove console box.
2) With ignition switch turned OFF, connect scan tool to DLC or connect voltage tester between “E52-18” –
“E52-9” (main sensor) or “E52-6” – “E52-9” (sub
sensor) with connected connector (1) to P/S control
module. 3) Set torque wrench to stee
ring wheel referring to
“Steering Force Check” for checking steering force.
4) Turn ON ignition switch without engine running and select scan tool “Data list” mode due to check of
“TQS Main Torque”, “TQS Sub Torque” and “Assist
Torque” display on scan tool when steering wheel
turned left and right (if used).
5) Check that characteristic of torque sensor (main and sub) output voltage or scan tool data and steering
force is as following graph when steering wheel is
turned left and right. If sensor voltage or scan tool
data is out of specified value or does not vary linearly
as the following graph, check P/S control module
and its circuit.
If they are OK, replace steering gear case assembly.
1
(a)
2
3
(b)
I7RS0A630020-01
[A]: Steering force at left turn
[B]: Steering force at right turn
[C]: Steering wheel at free
[D]: “TQS Main Torque”, “TQS Sub Torque” and “Assist Torque” in “Data List” displayed on scan tool
E52
18
9
6
9
6 18
1
I6RS0C630024-01
I3RM0A630022-01
0
[C] [N.m]
MAX MAX
[B]
[A]
2.33 - 2.68 [V]
[D]
0.65 - 0.72
(0 - 0.4)
4.21 - 4.41
(5.1 - 5.6)
6.86
-6.86
0
6.86
- 6.86
I6RS0C630021-04