Engine check light SUZUKI SWIFT 2008 2.G Service Manual Online

Downloaded from www.Manualslib.com manuals search engine Power Assisted Steering System: 6C-3
EPS Diagnosis General DescriptionS7RS0B6301002
The P/S system in this vehicle is controlled by the P/S control module. T he P/S control module has an on-board
diagnostic system which detects a malfunction in this system. When diagnosing troubles, be sure to have full
understanding of the outline of “On-Board Diagnostic Sy stem Description” and each item in “Precautions in
Diagnosing Troubles”, and then execute diagnosis according to “EPS System Check”.
On-Board Diagnostic System DescriptionS7RS0B6301003
The P/S control module performs the on -board diagnosis (self-diagnosis) on the system and operates the “EPS”
warning light (1) as follows.
• The “EPS” warning light lights when the ignition switch is turned to ON position (but the engine at stop) regardless
of the condition of the P/S co ntrol system. This is only to check if the “EPS” warning light is operated properly.
• If the areas monitored by the P/S control module is free from any trouble after the engine start (while engine is
running), the “EPS” warning light turns OFF.
• When the P/S control module detects a trouble which has occurred in th e monitored areas the “EPS” warning light
comes ON while the engine is running to warn the driver of such occurrence of the trouble and at the same time it
stores the exact trouble area in memory inside of the P/S control module.
Driving Cycle
A “Driving Cycle” consists of en gine startup and engine shutoff.
3 Driving Cycles Detection Logic
The malfunction detected in the first and second driving cycl e is stored in P/S control module memory (in the form of
pending DTC) but the “EPS” wa rning light does not light at these time. It lights up at t he third detection of same
malfunction also in the next driving cycle.
1
I6RS0C630002-01

Downloaded from www.Manualslib.com manuals search engine Power Assisted Steering System: 6C-5
Terminal Arrangement of P/S Control Module Coupler (Viewed from Harness Side)
Diagnostic Information and Procedures
EPS System CheckS7RS0B6304001
WARNING!
Carry out test drive in light traffic area to prevent an accident.

Refer to the following items for the details of each step.Terminal Circuit Terminal Circuit
E49-1 Main power supply for internal memory
and EPS motor E52-9 Ground for torque sensors
E49-2 Ground for P/S control module E52-10 —
E51-1 Motor output 1 E52-11 Serial communication for data link
connector
E51-2 Motor output 2 E52-12 Engine speed signal
E52-1 Ignition switch signal for P/S control
module E52-13 —
E52-2 — E52-14 P/S operation signal (idle up signal)
E52-3 — E52-15 —
E52-4 Vehicle speed signal E52-16 Torque sensor internal failure signal
E52-5 “EPS” warning light E52-17 —
E52-6 Torque sensor signal (Sub) E52-18 Torque sensor signal (Main)
E52-7 — E52-19 Ground for shield wire
E52-8 Main power supply for torque sensor E52-20 5 V reference power supply for torque
sensor
Step
Action YesNo
1 ) Customer complaint analysis
1) Perform customer complaint analysis referring to “Customer Complaint Analysis”.
Was customer complaint analysis performed? Go to Step 2.
Perform customer
complaint analysis.
2 ) DTC check, record and clearance
1) Check for DTC (including pending DTC) referring to “DTC Check”, Record and Clearance.
Is there any DTC(s)? Print DTC or write them
down and clear them by
referring to “DTC
Clearance” and go to
St ep 3 .Go to Step 4.
3 ) Visual inspection
1) Perform visual inspection referring to “Visual Inspection”.
Is there any faulty condition? Repair or replace
malfunction part, and go
to Step 11.
Go to Step 5.
4 ) Visual inspection
1) Perform visual inspection referring to “Visual Inspection”.
Is there any faulty condition? Repair or replace
malfunction part, and go
to Step 11.
Go to Step 8.
5 ) Trouble symptom confirmation
1) Confirm trouble symptom referring to “Trouble Symptom Confirmation”.
Is trouble symptom identified? Go to Step 6.
Go to Step 7.
6 ) 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 8.

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.

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

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

Downloaded from www.Manualslib.com manuals search engine Power Assisted Steering System: 6C-15
“EPS” Warning Light Does Not Come ON with Ignition Switch Turned ON before Engine StartsS7RS0B6304010
Wiring Diagram
Circuit Description
Operation (ON/OFF) of “EPS” warning light is controlled by P/S control module through combination meter.
If the P/S system is in good condition, P/S control module turns “ 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
MBLK
REDE51-1
E51-2
[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]
7
12V
E49-2BLK
[B ]
1 2
GRY
LT GRN
/BLK
E52-1
E52-5
E49-1
GRNGRNWHTBLK
WHY
G28-25G28-31
RED/BLK
8
3
4
4
5 6
4
4
1 2
4
9
I7RS0B630004-01
[A]: Connector “E52” (viewed from harness side) 2. Ignition switch6. “EPS” warning light
[B]: Connector “E49” (viewed from harness side) 3. Junction block assembly7. P/S control module
[C]: Connector “G28” (viewed from harness si de)4. Fuse 8. Individual circuit fuse box No.1
1. Main fuse box 5. Combination meter9. “EPS” warning light circuit
StepAction YesNo
1 1) Turn ignition switch ON.
Do the other warning lights come on? Go to Step 2.
“GRN”, “RED/BLK” wire
circuit or circuit fuse for
combination meter open
or short to ground.
2 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 3.
Repair or replace
defective circuit.
3 1) Remove combination meter and disconnect combination meter connector (“G28”) with ignition switch turned OFF.
2) Check for proper connection to the combination meter at “G28-31” terminal.
3) If OK, check voltage between “G28-31” (“RED/BLK” wire) terminal and body ground with ignition switch ON.
Is it 10 – 14 V? Go to Step 4.
“RED/BLK” wire circuit
open or short to ground.

Downloaded from www.Manualslib.com manuals search engine 6C-16 Power Assisted Steering System:
“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 Power Assisted Steering System: 6C-33
DTC C1155: P/S Control Module FailureS7RS0B6304021
Wiring Diagram
Refer to “DTC C1153: P/S Control Module Power Supply Circuit Voltage Low”.
DTC Detecting Condition and Trouble Area
DTC Troubleshooting DTC detecting condition Trouble area
Internal memory (EEPROM) is data error.
(In this case, MIL does not light up)
or
Internal circuit is faulty.
or
Power supply voltage of P/S control module exceeded
17.5 V.
(1 driving cycle detection logic) • Overcharged Battery
• P/S control module
Step
Action YesNo
1 Was “EPS System Check” performed? Go to Step 2.Go to “EPS System
Check”.
2 P/S control module power supply and ground circuit
check
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 3.
Repair or replace
defective circuit.
3 Battery voltage check
1) Check voltage between positive (+) battery terminal and
vehicle body ground with engine speed at 3000 rpm.
Is voltage 15.5 V or less? Replace P/S control
module.
Check charging system
referring to “Generator
Test (Overcharged
Battery Check) in
Section 1J”.

Downloaded from www.Manualslib.com manuals search engine 6C-36 Power Assisted Steering System:
Voltage Check1) Remove console box.
2) Check for voltage at each terminal with co nnectors connected to the P/S control module.
NOTE
As each terminal voltage is affected by the battery voltage, confirm if the battery voltage is 11 V or
more when ignition switch is ON.
*: The voltage of this circuit may not be checked by voltmeter. If so, use oscilloscope.

Terminal Wire colorCircuit Normal voltage Remarks
E49-1 GRN Main power supply for
internal memory and P/S
motor 10 – 14 V
—
E49-2 BLK Ground for P/S control
module Below 0.3 V
—
E51-1 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 “E51-1” and vehicle body ground
E51-2 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 “E51-2” and vehicle body ground
E52-1 LT GRN/BLK Ignition switch signal for P/S
control module 10 – 14 V Ignition switch ON
E52-2 — —— —
E52-3 — —— —
E52-4 PPL Vehicle speed signal *0 – 1 V
↑↓
8 – 14 V
(“Reference
waveform No.9”
under “Inspection of
ECM and Its Circuits in Section 1A”.) • Ignition switch ON
•Front left tire tu
rned quickly with right
tire locked
E52-5 GRY “EPS” warning light 0 V “EPS” warning light OFF
E52-6 BLU Torque sensor signal (Sub) About 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 – 6 V • Steering wheel with right turn
• Out put voltage varies linearly
depending on steering force
E52-7 — —— —
E52-8 GRN Main power supply for torque
sensor About 12 V• Ignition switch ON
• Check voltage between “E52-8” and
“E52-9” terminals
E52-9 BRN Ground for torque sensors Below 0.3 V —
E52-10 — —— —

Downloaded from www.Manualslib.com manuals search engine Power Assisted Steering System: 6C-45
8) Install steering gear case assembly referring to “Steering Gear Case Assembly Removal and
Installation”.
Steering Rack Plunger Removal and InstallationS7RS0B6306009
Removal
1) Remove gear case assembly referring to “Steering
Gear Case Assembly Removal and Installation”.
2) Loosen lock nut (1) with holding damper screw (2).
3) Remove lock nut (1), rack damper screw (2), rack plunger spring (3) and rack plunger (4).
Installation 1) Apply grease lightly to sliding part of plunger (1) against rack.
“A”: Grease 99000–25050 (SUZUKI Super
Grease E)
2) Install plunger and spring (2) as shown.
3) Apply thread lock cement to rack damper screw (3)
and tighten them as follows.
a) Tighten damper screw to 25 N ⋅m (2.5 kgf-m, 18.0
lb-ft).
b) Loosen damper screw until 180 °.
c) Retighten damper screw to 3.9 N ⋅m (0.39 kgf-m,
3.0 lb-ft).
d) After tightening rack damper screw to specified torque, turn it back by 7 ± 3°.
“B”: Thread lock cement 99000–32110
(Thread Lock Cement Super 1322)
Tightening torque
Rack damper screw (a): Tighten 25 N ⋅m (2.5
kgf-m, 18.0 lb-ft) and loosen 180° and then
tighten 3.9 N ⋅m (0.39 kgf-m, 3.0 lb-ft) and turn
it back by 7 ± 3° by the specified procedure. 4) Pinion rotation torque should be checked with rack
position centered.
Also, check if rack as a whole moves smoothly.
Special tool
(A): 09944–18310
Tightening torque
Rotation torquer of pinion (a): 2.0 N·m (0.2 kgf-
m, 1.5 lb-ft)
5) After adjustment, tighten lo ck nut to specified torque
with holding damper screw at the position.
Tightening torque
Rack damper screw lock nut (a): 64 N·m (6.4
kgf-m, 46.5 lb-ft)
6) Install gear case assembly referring to “Steering Gear Case Assembly Re moval and Installation”.
Steering Rack Plunger InspectionS7RS0B6306010
• Inspect rack plunger (1) for wear or damage.
• Inspect rack plunger spring (2) for deterioration.
I4RS0A630045-01
I4RS0A630046-01
I3RM0A630055-02
I4RS0A630047-01