engine symptom diagnosis SUZUKI SWIFT 2008 2.G Service Service Manual
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Page 671 of 1496

Downloaded from www.Manualslib.com manuals search engine Automatic Transmission/Transaxle: 5A-27
Road TestS7RS0B5104011
This test is to check if upshift, downshift and lock-up take place at specified speeds while actually driving vehicle on a
level road.
WARNING!
• Carry out test in very little traffic area to prevent an accident.
• Test requires 2 persons, a driver and a tester.
1) Warm up engine.
2) With engine running at idle, shift select lever “D” range.
3) Accelerate vehicle speed by depressing accelerator pedal gradually.
4) While driving in “D” range, check if gear shift and lock-up occur properly as shown in “Automatic Gear Shift Table”.
Troubleshooting 9 Proceed to “Trouble Diag
nosis 2” in “A/T Symptom
Diagnosis”.
Is trouble identified? Repair or replace faulty
parts.
Proceed to “Trouble
Diagnosis 3” in “A/T
Symptom Diagnosis”.
Step Action Yes No
Condition
Possible cause Correction / Reference Item
Unable to run in all range Faulty valve body component Replace valve body assembly.
Faulty oil pump Inspect. If NG, replace.
Seized or broken planetary gear Inspect. If NG, replace.
Faulty one-way No.2 clutch Inspect. If NG, replace.
Faulty forward clutch Inspect. If NG, replace.
Faulty reverse clutch Inspect. If NG, replace.
Faulty 1st and reverse brake Inspect. If NG, replace.
Damaged drive plate Inspect. If NG, replace.
Faulty torque converter Replace.
No gear shift as 3rd gear Malfunction of shift solenoid valve-A
and/or -B Inspect. If NG, replace.
Malfunction of timing solenoid valve Inspect. If NG, replace.
Malfunction of pressure control solenoid
valve Inspect. If NG, replace valve body assembly.
1
→ 2 upshift fails to
occur Malfunction of shif
t solenoid valve-B Inspect. If NG, replace.
Malfunction of output shaft speed
sensor Inspect. If NG, replace.
Malfunction of throttle position sensor Inspect. If NG, replace.
Malfunction of transmission range
sensor Inspect. If NG, replace.
Faulty valve body component Replace valve body assembly.
Faulty 2nd brake Inspect. If NG, replace.
Faulty one-way No.1 clutch Inspect. If NG, replace.
2
→ 3 upshift fails to
occur Malfunction of shif
t solenoid valve-A Inspect. If NG, replace.
Malfunction of output shaft speed
sensor Inspect. If NG, replace.
Malfunction of throttle position sensor Inspect. If NG, replace.
Malfunction of transmission range
sensor Inspect. If NG, replace.
Faulty valve body component Replace valve body assembly.
Faulty direct clutch Inspect. If NG, replace.
Page 678 of 1496

Downloaded from www.Manualslib.com manuals search engine 5A-34 Automatic Transmission/Transaxle:
A/T Symptom DiagnosisS7RS0B5104018
Trouble Diagnosis 1
Electrical repair
Condition Possible cause Correction / Reference Item
Excessive shift shock Shift solenoid valve-A and/or -B circuit
faulty Inspect circuit for open, short and intermittent.
If NG, repair.
Pressure control solenoid valve circuit
faulty Inspect circuit for open, short and intermittent.
If NG, repair.
Timing solenoid valve circuit faulty only
when N → D or 3 ↔ 4 shifting Inspect circuit for open, short and intermittent.
If NG, repair.
Output shaft speed sensor circuit faulty Inspect circuit for open, short and intermittent.
If NG, repair.
Input shaft speed sensor circuit faulty Inspect circuit for open, short and intermittent.
If NG, repair.
Transmission fluid temperature sensor
circuit faulty Inspect circuit for open, short and intermittent.
If NG, repair.
CAN communication circuit faulty Inspect circuit for open, short and intermittent.
If NG, repair.
Throttle position sensor circuit faulty Inspect circuit for open, short and intermittent
referring to “Electric Throttle Body Assembly
On-Vehicle Inspection in Section 1C”. If NG,
repair.
Crankshaft position sensor circuit faulty Inspect circuit for open, short and intermittent
referring to “DTC P0335: Crankshaft Position
(CKP) Sensor “A” Circuit in Section 1A”. If NG,
repair.
TCM Substitute a known-good TCM and recheck.
ECM Substitute a known-good ECM and recheck.
No gear shift as 3rd gear Shift solenoid valve-A and/or -B circuit
faulty Inspect circuit for open, short and intermittent.
If NG, repair.
Pressure control solenoid valve circuit
faulty Inspect circuit for open, short and intermittent.
If NG, repair.
Timing solenoid valve circuit faulty Inspect circuit for open, short and intermittent.
If NG, repair.
TCM Substitute a known-good TCM and recheck.
Poor 1
→ 2 shift Shift solenoid valve-B circuit faulty Inspect circuit for open, short and intermittent.
If NG, repair.
Output shaft speed sensor circuit faulty Inspect circuit for open, short and intermittent.
If NG, repair.
Transmission range sensor circuit faulty Inspect circuit for open, short and intermittent.
If NG, repair.
CAN communication circuit faulty Inspect circuit for open, short and intermittent.
If NG, repair.
Throttle position sensor circuit faulty Inspect circuit for open, short and intermittent
referring to “Electric Throttle Body Assembly
On-Vehicle Inspection in Section 1C”. If NG,
repair.
TCM Substitute a known-good TCM and recheck.
ECM Substitute a known-good ECM and recheck.
Page 817 of 1496

Downloaded from www.Manualslib.com manuals search engine Manual Transmission/Transaxle: 5B-3
Diagnostic Information and Procedures
Manual Transaxle Symptom DiagnosisS7RS0B5204001
Repair Instructions
Manual Transaxle Oil ChangeS7RS0B5206001
1) Before changing or inspecting oil, be sure to stop engine and lift vehicle horizontally.
2) With vehicle lifted up, check oil level and leakage. If leakage exists, correct it.
NOTE
Whenever vehicle is hoisted for any other
service work than oil change, also be sure to
check for oil leakage.
3) Remove oil filler plug (2).
4) Remove drain plug (1), and drain old oil. 5) Apply sealant to thread of drain plug (1), and tighten
it to specified torque.
“A”: Sealant 99000–31260 (SUZUKI Bond
No.1217G)
Tightening torque
Transaxle oil drain plug (a): 21 N·m (2.1 kgf-m,
15.5 lb-ft)
6) Pour new specified oil unt il oil level reaches bottom
of oil filler plug hole (3) as shown in figure.NOTE
It is highly recommended to use API GL-4
75W-90 gear oil.
Transaxle oil specification
: API GL-4 (For SAE classification, refer to
viscosity chart [A] in figure.)
Manual transaxle oil capacity
Reference: 2.0 liters (4.2/3.5 US/Imp. pt)
Condition Possible cause Correction / Reference Item
Gears slipping out of
mesh Worn shift fork shaft
Replace.
Worn shift fork or synchronizer sleeve Replace.
Weak or damaged locating springs Replace.
Worn bearings on input shaft or
countershaft Replace.
Worn chamfered tooth on sleeve and
gear Replace sleeve and gear.
Hard shifting Maladjusted gear select control cable Adjust.
Inadequate or insufficient lubricant Replenish.
Improper clutch pedal free travel Replace clutch master cylinder or clutch pedal
arm.
Distorted or broken clutch disc Replace.
Damaged clutch pressure plate Replace clutch cover.
Worn synchronizer ring Replace.
Worn chamfered tooth on sleeve or gear Replace sleeve or gear.
Worn gear shift / select control cables
joint Replace.
Distorted shift shaft Replace.
Worn gear shift / select control cables Replace.
Noise Inadequate or insufficient lubricant Replenish.
Damaged or worn bearing(s) Replace.
Damaged or worn gear(s) Replace.
Damaged or worn synchronizer parts Replace.
Page 854 of 1496

Downloaded from www.Manualslib.com manuals search engine 5C-2 Clutch:
Diagnostic Information and Procedures
Clutch System Symptom DiagnosisS7RS0B5304001
Repair Instructions
Clutch Pedal InspectionS7RS0B5306001
Cylinder Push Rod Play “A”1) Press clutch pedal (1) gradually with finger, stop when slight increase of resistance is felt and
measure how much pedal has moved (push rod
play) as represented by “A” as shown.
Push rod play
“A”: Max. 3 mm (0.12 in.)
2) If “A” is not within specification, replace master cylinder (3) or pedal arm (2). Clutch Pedal Free Travel “B”
1) Depress clutch pedal (1), stop the moment clutch resistance is felt, and measure how much pedal has
moved (clutch pedal free travel) as represented by
“B” in figure.
Clutch pedal free travel
“B”
: 2 – 8 mm (0.08 – 0.31 in.)
2) If “B” is not within specification, check pedal arm (2) and master cylinder (3) and replace defective part.
Condition Possible cause Correction / Reference Item
Slipping Improper clutch pedal free travel Replace master cylinder or clutch pedal arm.
Worn or oily clutch disc facing Replace disc.
Warped disc, pressure plate or flywheel
surface Replace disc, clutch cover or flywheel.
Weakened diaphragm spring Replace clutch cover.
Master cylinder piston or seal cup not
returning Replace master cylinder.
Dragging clutch Improper clutch pedal free travel Replace master cylinder or clutch pedal arm.
Weakened diaphragm spring, or worn
spring tip Replace clutch cover.
Rusted input shaft splines Lubricate.
Damaged or worn splines of transaxle
input shaft Replace input shaft.
Excessively wobbly clutch disc Replace disc.
Clutch facings broken or dirty with oil Replace disc.
Fluid leakage Repair or replace.
Clutch vibration Glazed (glass-like) clutch facings Repair or replace disc.
Clutch facings dirty with oil Replace disc.
Release bearing slides unsmoothly on
input shaft bearing retainer Lubricate or replace input shaft bearing
retainer.
Wobbly clutch disc, or poor facing
contact Replace disc.
Weakened torsion springs in clutch disc Replace disc.
Clutch disc rivets loose Replace disc.
Distorted pressure plate or flywheel
surface Replace clutch cover or flywheel.
Weakened engine mounting Replace engine mounting.
Loosened engine mounting bolt or nut Retighten engine mounting bolt or nut.
Noisy clutch Worn or broken release bearing Replace release bearing.
Input shaft front bearing worn down Replace input shaft bearing.
Excessive rattle of clutch disc hub Replace disc.
Cracked clutch disc Replace disc.
Pressure plate and diaphragm spring
rattling Replace clutch cover.
Grabbing clutch Clutch disc facings soaked with oil Replace disc.
Clutch disc facings excessively worn Replace disc.
Rivet heads showing out of facing Replace disc.
Weakened torsion springs Replace disc.
Page 867 of 1496

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
Page 870 of 1496

Downloaded from www.Manualslib.com manuals search engine 6A-1 Steering General Diagnosis:
Steeri ng
Steering General Diagnosis
Precautions
Precautions for Steering DiagnosisS7RS0B6100001
Since the problems in steering involve several systems, they must all be considered when diagnosing a complaint. To
avoid using the wrong symptom, always road test the vehicl e first. Proceed with the following preliminary inspection
and correct any defects which are found.
1) Inspect tires for proper pressure and uneven wear.
2) Raise vehicle on a hoist and inspect steering system for loose or damaged parts.
3) Spin front wheels. Inspect for out-of-round tires, out- of-balance tires, bent rims, loosen and/or rough wheel
bearings.
Page 871 of 1496

Downloaded from www.Manualslib.com manuals search engine Steering General Diagnosis: 6A-2
Diagnostic Information and Procedures
Steering Symptom DiagnosisS7RS0B6104001
ConditionPossible cause Correction / Reference Item
Hard steering Tire not adequately inflated Inflate tires to proper pressure.
Malfunction of power steering system Check and correct.
Bind in tie-rod end ball studs or lower
ball joints Replace tie-rod end or front suspension arm.
Disturbed front wheel alignment Check and adjust front wheel alignment.
Bind in steering column Repair or replace steering column.
Rack and pinion adjustment Check and adjustment rack and pinion torque.
Too much play in steering Wheel bearings worn Replace wheel bearing.
Loose steering gear case bolts Tighten gear case bolts.
Faulty steering gear case assembly Replace steering gear case assembly.
Worn steering shaft joints Replace joint.
Worn tie-rod ends or tie-rod inside ball
joints Replace tie-rod end or tie-rod.
Worn lower ball joints Replace front suspension control arm.
Rack and pinion adjustment Check and adjustment rack and pinion torque.
Poor return ability Bind in tie-rod end ball studs Replace tie-rod end.
Bind in ball joints Replace front suspension control arm.
Bind in steering column Repair or replace steering column.
Disturbed front end alignment Check and adjust front end alignment.
Faulty steering gear case assembly Replace steering gear case assembly.
Tires not adequately inflated Adjust tire pressure.
Rack and pinion adjustment Check and adjustment rack and pinion torque.
Rack and pinion noise
(Rattle or chuckle) Loose steering gear case bolts
Tighten steering gear case bolts.
Rack and pinion adjustment Check and adjustment rack and pinion torque.
Faulty steering gear case assembly Replace steering gear case assembly.
Broken or other wise damaged wheel
bearing(s) Replace wheel bearing(s).
Wander or poor steering
stability Mismatched or uneven tires
Replace or inflate tires to proper pressure.
Loosen ball joints and tie-rod ends Replace suspension control arm or tie-rod end.
Faulty struts or mountings Replace strut or repair mounting.
Loose stabilizer bar Tighten or replace stabilizer bar or bush.
Broken or sagging springs Replace spring.
Rack and pinion adjustment Check and adjustment rack and pinion torque.
Disturbed front wheel alignment Check and adjust front wheel alignment.
Faulty steering gear case assembly Replace steering gear case assembly.
Erratic steering when
braking Worn wheel bearing(s)
Replace wheel bearing(s).
Broken or sagging spring(s) Replace coil spring(s).
Wheel tires are inflated unequally Inflate tires to proper pressure.
Disturbed front wheel alignment Check and adjust front wheel alignment.
Brakes not working in unison Check and repair brake system.
Leaking caliper Repair or replace caliper.
Warped discs Replace brake disc.
Badly worn brake pads Replace brake pads.
Page 888 of 1496

Downloaded from www.Manualslib.com manuals search engine 6C-6 Power Assisted Steering System:
NOTE
• As execution of “DTC Clearance” will clear all DTCs, be sure to record all DTCs before service.
• DTC C1122 is indicated when ignition switch is at ON position and engine is not running, it means
that nothing is abnormal.
• Current DTC and history DTC ca n be identified by condition of the “EPS” warning light.
“EPS” warning light operates as follows.
7 ) Rechecking and record of DTC
1) Recheck for DTC referring to “DTC Check”.
Is there any DTC(s)? Go to Step 9. Go to Step 10.
8 ) Steering symptom diagnosis and P/S system
symptom diagnosis
1) Check and repair according to “Steering Symptom Diagnosis in Section 6A” and “P/S System Symptom
Diagnosis”.
Are check and repair complete? Go to Step 11. Check and repair
malfunction part(s), and
go to Step 11.
9 ) Troubleshooting for DTC
1) Check and repair according to applicable DTC diag. flow.
Are check and repair complete? Go to Step 11. Check and repair
malfunction part(s), and
go to Step 11.
10 ) Intermittent problems check
1) Check for intermittent problems referring to “Intermittent Problems Check”.
Is there any faulty condition? Repair or replace
malfunction part(s), and
go to Step 11.
Go to Step 11.
11 ) Final confirmation test
1) Clear DTC if any.
2) Perform final confirmation test referring to “Final Confirmation Test”.
Is there any problem symptom, DTC or abnormal condition? Go to Step 6. End.
Step Action Yes No
Current DTC is set.
(Abnormality exists at
present.)
Only history DTC is set.
(Faulty condition occurred once
in the past, but normal condition
is detected at present.)
Current and history DTC
exist.
“EPS” warning light
after engine started Remains ON. Turns OFF. Remains ON.
Page 890 of 1496

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
Page 894 of 1496

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”.