Part SUZUKI SWIFT 2008 2.G Service Owner's Guide

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Diagnostic Information and Procedures
Engine and Emission Control System CheckS7RS0B1104001
Refer to the following items for the details of each step.Step Action Yes No 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 / Freeze frame data check, record and clearance
1) Check for DTC (including pending DTC) referring to “DTC / Freeze Frame Data Check, Record and
Clearance”.
Is there any DTC(s)? Print DTC and freeze
frame data 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 / Freeze frame data
1) Recheck for DTC and freeze frame data referring to “DTC Check”.
Is there any DTC(s)? Go to Step 9.
Go to Step 8.
7 ) Rechecking and record of DTC / Freeze frame data
1) Recheck for DTC and freeze frame data referring to “DTC Check”.
Is there any DTC(s)? Go to Step 9.
Go to Step 10.
8 ) Engine basic inspection and engine symptom
diagnosis
1) Check and repair according to “Engine Basic Inspection”
and “Engine 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.

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Step 2: DTC / Freeze Frame Data Check, Record and
Clearance
First, check DTC (including pending DTC), referring to
“DTC Check”. If DTC is indicated, print it and freeze
frame data 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 sy mptom 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 engine
referring to “Visual Inspection”.
Step 5: Trouble Symptom Confirmation
Based on information obtained in “Step 1: Customer
Complaint Analysis: ” and “Step 2: DTC / Freeze Frame
Data Check, Record and Clearance: ”, confirm trouble
symptoms. Also, reconfirm DTC according to “DTC
Confirmation Procedure” described in each DTC diag.
flow.
Step 6 and 7: Rechecking and Record of DTC /
Freeze Frame Data
Refer to “DTC Check” for checking procedure.
Step 8: Engine Basic Inspection and Engine
Symptom Diagnosis
Perform basic engine check according to “Engine Basic
Inspection” first. When the end of the flow has been
reached, check the parts of the system suspected as a
possible cause referring to “Engine Symptom Diagnosis”
and based on symptoms appearing on the vehicle
(symptoms obtained through steps of customer
complaint analysis, trouble symptom confirmation and/or
basic engine 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, ECM or other part and repair or
replace faulty parts. Step 10: Intermittent Problems Check
Check parts where an intermit
tent trouble is easy to
occur (e.g., wire harness, connector, etc.), referring to
“Intermittent and Poor Connec tion 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
engine is free from any abnormal conditions. If what has
been repaired is re lated to the DTC, clear the DTC once,
perform DTC confirmation procedure and confirm that no
DTC is indicated.
Malfunction Indicator Lamp (MIL) CheckS7RS0B1104002
1) Turn ON ignition switch (with engine at stop) and check that MIL (1) lights.
If MIL does not light up (or MIL dims) but engine can
be starting, go to “MIL Does Not Come ON with
Ignition Switch ON and Engine Stop (but Engine Can
Be Started)” for troubleshooting.
If MIL does not light with ignition switch ON and
engine does not start though it is cranked up, go to
“ECM Power and Ground Circuit Check”.
2) Start engine and check that MIL turns OFF. If MIL remains ON and no DTC is stored in ECM, go
to “Malfunction Indicator Lamp Remains ON after
Engine Starts” for troubleshooting.
1
I4RS0A110012-01

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Scan Tool DataS7RS0B1104007
As the data values are standard values estimated on the basis of values obtained from the normally operating vehicles
by using a scan tool, use them as re ference values. Even when the vehicle is in good condition, there may be cases
where the checked value does not fall within each specified data range. Therefore, judgment as abnormal should not
be made by checking with these data alone.
Also, conditions that can be checked by the scan tool are those detected by ECM and output from ECM as commands
and there may be cases where the engine or actuator is not operating (in the condition) as indicated by the scan tool.
Be sure to use the timing light to check the ignition timing.
NOTE
• There are two types of OBD system depending on the vehicle specification.
For details, refer to “Precaution on On-Board Diagnostic (OBD) System”.
• With the generic scan tool, only star (*) marked data in the following table can be read.
• When checking the data with the engine running at idle or racing, be sure to shift M/T gear to the neutral position and A/T gear to the “Park” position and pull the parking brake fully. Also, if nothing
or “no load” is indicated, turn O FF A/C (if equipped with A/C), all electric loads, P/S and all the other
necessary switches.

) P2122 Throttle/pedal position sensor/switch/“D” (main)
circuit low input
• ECM turns off throttle actuator control relay and throttle valve is fixed at the specified opening from
its completely closed position (default opening).
For details, refer to “Description of Electric
Throttle Body System”.
• ECM controls fuel cut at specified engine speed.
• ECM stops air/fuel ratio control.
)
P2123 Throttle/pedal position sensor/switch/“D” (main)
circuit high input
) P2127 Throttle/pedal position sensor/switch/“E” (sub)
circuit low input
) P2128 Throttle/pedal position sensor/switch/“E” (sub)
circuit high input
) P2135 Throttle/pedal position sensor/switch/“A”/“B”
(main) / (sub) voltage correction
) P2138 Throttle pedal position sensor/switch “D”/“E”
(main) / (sub) voltage correlation
) P2227 Barometric pressure sensor performance problem ECM controls actuators assuming that barometric
pressure is 101.33 kPa (762 mmHg).
DTC No. Detected item Fail-safe operation
Scan tool data
Vehicle condition Normal condition /
reference values
* ) COOLANT TEMP At specified idle speed after warming up 80 – 100 °C, 176 – 212 °F
* ) INTAKE AIR TEMP. At specifie d idle speed after warming up –5
°C (23 °F) + environmental
temp. to 40 °C (104 °F) +
environmental temp.
* ) ENGINE SPEED It idling with no load after warming upDesired idle speed ± 50 rpm
) INJ PULSE WIDTH At specified idle speed with no load after warming up
2.0 – 4.0 msec.
At 2500 r/min. with no load after warming up 2.0 – 3.6 msec.
) DESIRED IDLE It idling with radiator cooling fan stopped and all electrical
parts turned OFF after warming up, M/T at neutral 700 rpm
* ) SHORT FT B1 At specified idle speed after warming up –20 – +20%
* ) LONG FT B1 At specified idle speed after warming up –20 – +20%
) TOTAL FUEL TRIM
B1 At specified idle speed after warming up
–35 – +35%
* ) MAF At specified idle speed wit
h no load after warming up 1.0 – 4.0 g/s 0.14 – 0.52 lb/
min.
At 2500 r/min. with no load after warming up 4.0 – 12.0 g/s 0.53 – 1.58 lb/
min.
* ) CALC LOAD At specified idle speed with no load after warming up
18 – 28%
At 2500 r/min. with no load after warming up 13 – 23%
* )
THROTTLE
POSITION Ignition switch ON /
warmed up engine
stoppedAccelerator pedal released
0 – 5%
Accelerator pedal depressed
fully 90 – 100%

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TP SENSOR 2 VOLT (THROTTLE POSITION SENSOR
(SUB) OUTPUT VOLTAGE, V)
The TP sensor (sub) reading provides throttle valve
opening information in the form of voltage.
APP SENSOR 1 VOLT (ACCELERATOR PEDAL
POSITION (APP) SENSOR (MAIN) OUTPUT
VOLTAGE, V)
The APP sensor (main) read ing provides accelerator
pedal opening information in the form of voltage.
APP SENSOR 2 VOLT (ACCELERATOR PEDAL
POSITION (APP) SENSOR (S UB) OUTPUT VOLTAGE,
V)
The APP sensor (sub) reading provides accelerator
pedal opening information in the form of voltage.
ACCEL POSITION (ABSOLUTE ACCELERATOR
PEDAL POSITION, %)
When accelerator pedal is at fully released position,
accelerator pedal is indicated as 0 – 5% and 90 – 100%
fully depressed position. THROTTLE TARGET POSI (TARGET THROTTLE
VALVE POSITION, %)
Target throttle valve position is ECM internal parameter
which indicates the ECM requested throttle valve
position.
BATTERY CURRENT (A)
This parameter indicates elec
tric load value (current
consumption) that detected by electric load current
sensor.
GENERATOR CONT DUTY (GENERATOR CONTROL
DUTY, %)
This parameter indicates generator control duty ratio that
controls production electricity of generator by ECM.
100%: No limitation for the generating
0%: Maximum limitation for the generating
GENERATOR FIELD DUTY (GENERATOR FIELD
COIL DUTY, %)
This parameter indicates ope rating rate (status of
production electricity) for gen erator by field coil duty
ratio.
100%: maximum operation.
0%: minimum operation.
Visual InspectionS7RS0B1104008
Visually check the following parts and systems.
Inspection item Reference section
• Engine oil – level, leakage “Engine Oil and Filter Change in Section 0B”
• Engine coolant – level, leakage “Co olant Level Check in Section 1F”
• Fuel – level, leakage “Fuel Lines and Connections Inspection in Section 0B”
• Air cleaner element – dirt, clogging “Air Cleaner Filter Inspection in Section 0B”
• Battery – fluid level, corrosion of terminal “Battery Description in Section 1J”
• Water pump belt – tension damage “Accessory Drive Belt Inspection in Section 0B”
• Throttle valve – operating sound “Electric Throttle Body Assembly On-Vehicle Inspection in Section 1C”
• Vacuum hoses of air intake system – disconnection, looseness,
deterioration, bend “Vacuum Hose and Purge Valve Chamber
Inspection in Section 1B”
• Connectors of electric wire harness – disconnection, friction
• Fuses – burning
• Parts – installation, bolt – looseness
• Parts – deformation
• Other parts that can be checked visually
Also check the following items at engine start, if possible
• Malfunction indicator lamp – Operation “Malfunction Indicator Lamp (MIL) Check”
• Charge warning lamp – Operation “Genera tor Symptom Diagnosis in Section 1J”
• Engine oil pressure warning lamp – Operation “O il Pressure Switch Inspection in Section 9C”
• Engine coolant temp. meter – Operation “ECT Sensor Inspection in Section 1C”
• Fuel level meter – Operation “Fuel Level Sensor Inspection in Section 9C”
• Tachometer – Operation
• Abnormal air being inhaled from air intake system
• Exhaust system – leakage of exhaust gas, noise
• Other parts that can be checked visually

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8Check ignition timing
1) Using SUZUKI scan tool, select “Misc Test” mode on
SUZUKI scan tool and fix ignition timing to initial one.
2) Using timing light (1), check initial ignition timing. Special tool
(A): 09930–76420
Is it 5
°± 3° BTDC at specif ied idle speed? Go to “Engine Symptom
Diagnosis”.
Check ignition control
related parts referring to
“Ignition Timing
Inspection in Section
1H”.
9 Check immobilizer system malfunction
1) Check immobilizer indica tor lamp for flashing.
Is it flashing when ignition switch is turned to ON position? Go to “Diagnostic
Trouble Code (DTC)
Check in Section 10C”.
Go to Step 10.
10 Check fuel supply
1) Check to make sure that enough fuel is filled in fuel tank.
2) Turn ON ignition switch for 2 seconds and then OFF.
3) Repeat Step 2) a few times.
Is fuel pressure felt from fuel feed hose when ignition switch
is turned ON? Go to Step 12. Go to Step 11.
Step Action Yes No
I2RH01110006-01
1, (A)
10
0I3RB0A180004-01
I3RM0A110014-01

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Engine Symptom DiagnosisS7RS0B1104010
Perform troubleshooting referring to the followings when ECM has detected no DTC and no abnormality has been
found in “Visual Inspection” and “Engine Basic Inspection”.
Condition Possible cause Correction / Reference Item
Hard starting (Engine
cranks OK) Faulty spark plug
“Spark Plug Inspection in Section 1H”
Leaky high-tension cord “High-Tension Cord Inspection in Section 1H”
Loose connection or disconnection of
high-tension cord(s) or lead wire(s) “High-Tension Cord Removal and Installation
in Section 1H”
Faulty ignition coil “Ignition Coil Assembly (Including ignitor)
Inspection in Section 1H”
Dirty or clogged fuel hose or pipe “Fuel Pressure Check”
Malfunctioning fuel pump “Fuel Pressure Check”
Air drawn in through intake manifold
gasket or throttle body gasket
Faulty electric throttle body assembly “Electric Throttle Body Assembly On-Vehicle
Inspection in Section 1C”
Faulty APP sensor assembly “APP Sensor Assembly Inspection in Section
1C”
Faulty ECT sensor or MAF sensor “ECT Sensor Inspection in Section 1C” or
“MAF and IAT Sensor Inspection in Section
1C”
Faulty ECM
Low compression “Compression Check in Section 1D”
Poor spark plug tightening or faulty
gasket “Spark Plug Removal and Installation in
Section 1H”
Compression leak from valve seat “Valves and Valve Guides Inspection in
Section 1D”
Sticky valve stem “Valves and Valve Guides Inspection in
Section 1D”
Weak or damaged valve springs “Valve Spring Inspection in Section 1D”
Compression leak at cylinder head
gasket “Cylinder Head Inspection in Section 1D”
Sticking or damaged piston ring “Cylinders, Pistons and Piston Rings
Inspection in Section 1D”
Worn piston, ring or cylinder “Cylinders, Pistons and Piston Rings
Inspection in Section 1D”
Malfunctioning PCV valve “PCV Valve Inspection in Section 1B”
Camshaft position control (VVT) system
out of order “Oil Control Valve Inspection in Section 1D”
Faulty EGR system “EGR System Inspection in Section 1B”
Low oil pressure Improper oil viscosity “Engine Oil and Filter Change in Section 0B”
Malfunctioning oil pressure switch “Oil Pressure Switch Inspection in Section 9C”
Clogged oil strainer “Oil Pan and Oil Pump Strainer Cleaning in
Section 1E”
Functional deterioration of oil pump “Oil Pump Inspection in Section 1E”
Worn oil pump relief valve “Oil Pump Inspection in Section 1E”
Excessive clearance in various sliding
parts
Engine noise – Valve
noise
NOTE
Before checking
mechanical noise, make
sure that:
• Specified spark plug is used.
• Specified fuel is used.

Improper valve lash “Camshaft, Tappet and Shim Inspection in
Section 1D”
Worn valve stem and guide “Valves and Valve Guides Inspection in
Section 1D”
Weak or broken valve spring “Valve Spring Inspection in Section 1D”
Warped or bent valve “Valves and Valve Guides Inspection in
Section 1D”

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1) With ignition switch turned OFF, connect scan tool.
2) Turn ON ignition switch and print Freeze Frame Data or write them down using scan tool.
3) Clear DTC using scan tool.
4) Start engine and warm up to normal operating temperature.
5) Operate vehicle with condition as noted freeze frame data for 5 min.
6) Stop vehicle and check DTC and pending DTC.
DTC Troubleshooting
NOTE
• When measuring circuit voltage, resistance and/ or pulse signal at ECM connector, connect the
special tool to ECM and/or the ECM connectors re ferring to “Inspection of ECM and Its Circuits”.
• Upon completion of inspection and repair work, perform “DTC Confirmation Procedure” and confirm that the trouble has been corrected.

Step Action YesNo
1 Was “Engine and Emission Control System Check”
performed? Go to Step 2.
Go to “Engine and
Emission Control
System Check”.
2 Is there DTC(s) other than fuel system (DTC P0171 /
P0172)? Go to applicable DTC
diag. flow.Go to Step 3.
3 Intake system and exhaust system for leakage check
Are intake system and exhaust system in good condition? Go to Step 4.
Repair or replace
defective part.
4 Fuel pressure check
1) Check fuel pressure referring to “Fuel Pressure Check”.
Is check result satisfactory? Go to Step 5.
Repair or replace
defective part.
5 Fuel injectors and its circuit check
1) Check fuel injectors referring to “Fuel Injector Inspection
in Section 1G”.
Is check result satisfactory? Go to Step 6.
Faulty injector(s) or its
circuit.
6 Visual inspection
1) Check MAF sensor and air intake system.
• Objects which block measur ing duct and resistor of
MAF sensor.
• Other air flow which does not pass MAF sensor.
Are they in good condition? Go to Step 7.
Repair or replace
defective part.
7 MAF sensor for performance check
1) With ignition switch turn ed OFF, install scan tool.
2) Start engine and warm up to normal operating temperature.
3) Check MAF value using scan tool (Refer to “Scan Tool Data” for normal value.).
Is each value within specified range? Go to Step 8.
Go to “DTC P0101:
Mass or Volume Air
Flow Circuit Range /
Performance”.
8 ECT sensor for performance check
1) Check ECT sensor referring to Step 3 and 4 of “DTC
P0118: Engine Coolant Temperature Circuit High”.
Is check result satisfactory? Go to Step 9.
Faulty ECT sensor or its
circuit.

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DTC Troubleshooting
NOTE
• When measuring circuit voltage, resistance and/or pulse signal at ECM connector, connect the
special tool to ECM and/or the ECM connectors re ferring to “Inspection of ECM and Its Circuits”.
• Upon completion of inspection and repair work, perform “DTC Confirmation Procedure” and confirm that the trouble has been corrected.

Step Action YesNo
1 Was “Engine and Emission Control System Check”
performed? Go to Step 2.
Go to “Engine and
Emission Control
System Check”.
2 Does fuel level meter in dicate “E” level (empty)? Add fuel and recheck. Go to Step 3.
3 Fuel quality check
1) Check that there is fuel of good quality in the fuel tank.
Is it OK? Go to Step 4.
Clean in fuel system
circuit and change fuel.
4 Ignition system check
1) Check spark plug and ignition spark of cylinder where
misfire occurs, referring to “Spark Plug Inspection in
Section 1H” and “Ignition Spark Test in Section 1H”.
Are they in good condition? Go to Step 5.
Faulty ignition coil, wire
harness, spark plug or
other system parts.
5 Fuel injector circuit check
1) Using sound scope, check each injector operating sound
at engine cranking or idling.
Do all injectors ma ke operating sound? Go to Step 6.
Check coupler
connection and wire
harness of injector not
making operating sound
and injector itself. If OK,
substitute a known-
good ECM and recheck.
6 Fuel pressure check
1) Check fuel pressure referring to “Fuel Pressure Check”.
Is check result satisfactory? Go to Step 7.
Repair or replace fuel
system.
7 Fuel injector check
1) Check fuel injector(s) re ferring to “Fuel Injector
Inspection in Section 1G”.
Is check result satisfactory? Go to Step 8.
Replace defective
injector.
8 Ignition timing check
1) Check ignition timing referring to “Ignition Timing
Inspection in Section 1H”.
Is check result satisfactory? Go to Step 9.
Check related sensors.
9 EGR system check
1) Check EGR system referring to “EGR System Inspection
in Section 1B”.
Is check result satisfactory? Go to Step 10. Repair or replace EGR
system.
10 Exhaust system check
1) Check exhaust system for exhaust gas clogged.
Is it OK? Go to Step 11. Repair clogged of
exhaust system.

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DTC P0327 / P0328: Knock Sensor 1 Circuit Low / HighS7RS0B1104040
Wiring Diagram
DTC Detecting Condition and Trouble Area
DTC Confirmation Procedure1) Connect scan tool to DLC with ignition switch turned OFF.
2) Turn ON ignition switch and clear DTC by using scan tool.
3) Start engine and run it for 10 sec.
4) Check DTC by using scan tool. 11
Engine mechanical system check
1) Check engine mechanical parts or system which can
cause engine rough idle or poor performance.
• Engine compression (Refer to “Compression Check in Section 1D”.)
• Valve lash (Refer to “Valve Lash (Clearance) Inspection in Section 1D”.)
• Valve timing (Refer to “Timing Chain and Chain Tensioner Removal and Installation in Section 1D”.)
Are they in good condition? Check wire harness and
connection of ECM
ground, ignition system
and fuel injector for
intermittent open and
short.
Repair or replace
defective part.
Step
Action YesNo
E23 C37
34
1819
567
1011
17
20
47 46
495051
2122
52 16
25 9
24
14
29
55
57 54 53
59
60 58 2
262728
15
30
56 4832 31
34353637
40
42 39 38
44
45 43 41 331
1213
238
34
1819
567
1011
17
20
47 46
495051
2122
52 16
25 9
24
14
29
55
57 54 53
59
60 58 2
262728
15
30
56 4832 31
34353637
40
42 39 38
44
45 43 41 331
1213
238
1 2
REDC37-56
5 V
I4RS0A110031-01
1. Knock sensor
2. ECM
DTC detecting condition Trouble area
DTC P0327:
Voltage of knock sensor is less than 1.23 V for 0.5 seconds
continuously.
(1 driving cycle detection logic)
DTC P0328:
Voltage of knock sensor is 3.91 V or more for 0.5 seconds
continuously
(1 driving cycle detection logic) • Knock sensor circuit (open or short)
• Knock sensor
•ECM

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DTC Detecting Condition and Trouble Area
DTC Confirmation Procedure
WARNING!
• When performing a road test, select a place where there is no traffic or possibility of a traffic accident and be very careful during testing to avoid occurrence of an accident.
• Road test should be carried out by 2 persons, a driver and a tester, on a level road.

NOTE
Check to make sure that following conditions ar e satisfied when using this “DTC Confirmation
Procedure”.
• Intake air temperature at engine start: –10 °C (14 ° F) to 80 °C (176 °F)
• Intake air temperature: –10 °C (14 °F) to 70 °C (158 °F)
• Engine coolant temp.: 70 °C, 158 °F to 150 °C (302 °F)
• Altitude (barometric pressure): 2400 m, 8000 ft or less (500 mmHg, 75 kPa or more)

1) Connect scan tool to DLC with ignition switch turned OFF.
2) Turn ON ignition switch and clear DTC using scan tool.
3) Increase vehicle speed to 37 – 62 mph, 60 – 100 km/h. (engine speed: 2500 – 3000 r/min.)
4) Keep above vehicle speed for 10 min. or more (Thr ottle valve opening is kept constant in this step).
5) Stop vehicle and check if DTC / pending DTC exists using sc an tool. If not, check if catalyst monitoring test has
been completed using scan tool. If not in both of above checks (i.e., no DTC / pending DTC and catalyst
monitoring test not completed), check vehicle cond ition (environmental) and repeat Step 3) through 5).
DTC Troubleshooting
NOTE
• When measuring circuit voltage, resistance and/ or pulse signal at ECM connector, connect the
special tool to ECM and/or the ECM connectors re ferring to “Inspection of ECM and Its Circuits”.
• Upon completion of inspection and repair work, perform “DTC Confirmation Procedure” and confirm that the trouble has been corrected.

DTC detecting condition Trouble area
Response delay of HO2S-2 signal (shifting delay from rich to lean and
from lean to rich with threshold at 0.45 V) compared to switching cycle
(rich-lean) of A/F feed back is less than specified while vehicle is
running at constant speed and except with high engine load after
warmed up.
(*2 driving cycle detection logic, monitoring once per driving cycle) • Exhaust gas leak
• Warm up three way catalytic converter
malfunction
• HO2S-2 malfunction
• HO2S-1 malfunction
Step Action YesNo
1 Was “Engine and Emission Control System Check”
performed? Go to Step 2.
Go to “Engine and
Emission Control
System Check”.
2 Exhaust system visual check
1) Check exhaust system for leaks, damage and loose
connection.
Is it in good condition? Go to Step 3.
Repair or replace
defective part.