Exhaust System SUZUKI SX4 2006 1.G Service User Guide

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General Description
Statement on Cleanliness and CareS6RW0D1101001
An automobile engine is a combination of many
machined, honed, polished and lapped surfaces with
tolerances that are measured in the thousands of an
millimeter (ten thousands of an inch).
Accordingly, when any internal engine parts are
serviced, care and cleanliness are important.
It should be understood that proper cleaning and
protection of machined surfaces and friction areas is part
of the repair procedure. This is considered standard
shop practice even if not specifically stated.
• A liberal coating of engine oil should be applied to
friction areas during assembly to protect and lubricate
the surfaces on initial operation.
• Whenever valve train components, pistons, piston
rings, connecting rods, rod bearings, and crankshaft
journal bearings are removed for service, they should
be retained in order.
At the time of installation, they should be installed in
the same locations and with the same mating
surfaces as when removed.
• Battery cables should be disconnected before any
major work is performed on the engine.
Failure to disconnect cables may result in damage to
wire harness or other electrical parts.
• The four cylinders of the engine are identified by
numbers; No.1 (1), No.2 (2), No.3 (3) and No.4 (4)
counted from crankshaft pulley side to flywheel side.
Engine Diagnosis General DescriptionS6RW0D1101002
NOTE
There are two types of OBD system
depending on the vehicle specification.
For identification, refer to “Precaution on On-
Board Diagnostic (OBD) System”.

This vehicle is equipped with an engine and emission
control system which are under control of ECM.
The engine and emission control system in this vehicle
are controlled by ECM. ECM has an On-Board
Diagnostic system which detects a malfunction in this
system and abnormality of those parts that influence the
engine exhaust emission. When diagnosing engine
troubles, be sure to have full understanding of the outline
of “On-Board Diagnostic System Description” and each
item in “Precautions in Diagnosing Trouble” and execute
diagnosis according to “Engine and Emission Control
System Check”.
There is a close relationship between the engine
mechanical, engine cooling system, ignition system,
exhaust system, etc. and the engine and emission
control system in their structure and operation. In case of
an engine trouble, even when the malfunction indicator
lamp (MIL) doesn’t turn ON, it should be diagnosed
according to “Engine and Emission Control System
Check”.
On-Board Diagnostic System DescriptionS6RW0D1101003
NOTE
There are two types of OBD system
depending on the vehicle specification.
For identification, refer to “Precaution on On-
Board Diagnostic (OBD) System”.

Euro OBD model
ECM in this vehicle has the following functions.
• When the ignition switch is turned ON with the engine
at a stop, malfunction indicator lamp (MIL) (1) turns
ON to check the circuit of the malfunction indicator
lamp (1).
• When ECM detects a malfunction which gives an
adverse effect to vehicle emission while the engine is
running, it makes the malfunction indicator lamp (1) in
the meter cluster of the instrument panel turn ON or
flash (flashing only when detecting a misfire which
can cause damage to the catalyst) and stores the
malfunction area in its memory.
(If it detects that continuously 3 driving cycles are
normal after detecting a malfunction, however, it
makes MIL (1) turn OFF although DTC stored in its
memory will remain.)
1
234
I3RM0A110001-01

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Engine and Emission Control System Flow Diagram
Intake manifoldExhaust
manifold
Exhaust gas Air
Fuel Vapor
War m up
catalystExhaust
pipe
EVAP canister
purge valve
Fuel injector
ECT
sensor
ECM
Heater
control
Heater
control
(if equipped)
Barometric pressure sensor HO2S-1HO2S-2
(if equipped) Engine
CMP
sensorCKP
sensor
Knock
sensorIgnition
coil with
igniter
APP sensor
A/C compressor
clutch
Generator
Immobilizer
coil antenna
P/S control
module
Brake light
switch
Air cleaner
IAT
sensorMAF
sensor
A/C refrigerant
pressure sensor
TP
sensor Throttle body
assembly
Throttle
actuator
A/C condenser
fan
DLC
Radiator
fan
Combination meter
· MIL
· Coolant Temp.
· Immobilizer indicator light
· Tachometer
· Speedometer
· Fuel level
· Odometer4WD
control module
Wheel speed
sensor (VSS)
(M/T)
· Electric load
· A/C switch ON
BCM
Keyless start
control module
ABS control module
Blower speed
selector
MAP sensor
(if equipped)EGR valve
(if equipped)
Check
valve
EVAP
canister
Fuel level sensorFuel tankFuel
pump
CMP actuator
oil control valve
(VVT model)
TCM
Output shaft speed
(VSS) sensor (A/T)
Three way
catalyst (if
equipped)
I6RW0D110004-03

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-33
) *P0117Engine coolant temperature circuit
lowCircuit voltage of ECT sensor is less than specification.1 driving
cycle
) *P0118Engine coolant temperature circuit
highCircuit voltage of ECT sensor is more than specification.1 driving
cycle
) *P0122Throttle position sensor (main)
circuit lowOutput voltage of throttle position sensor (main) is lower
than specification.1 driving
cycle
) *P0123Throttle position sensor (main)
circuit highOutput voltage of throttle position sensor (main) is higher
than specification.1 driving
cycle
)
U*P0131O2 sensor (HO2S) circuit low
voltage (Sensor-1)Max. output voltage of HO2S-1 is less than specification.2 driving
cycles
)
U*P0132O2 sensor (HO2S) circuit high
voltage (Sensor-1)Min. output voltage of HO2S-1 is more than specification.2 driving
cycles
)
U*P0133O2 sensor (HO2S) circuit slow
response (Sensor-1)Response time of HO2S-1 output voltage between rich
and lean is longer than specification.2 driving
cycles
) *P0134O2 sensor (HO2S) circuit no activity
detected (Sensor-1)Output voltage of HO2S-1 is more than specification or
less than specification. (or HO2S-1 circuit open or short)2 driving
cycles
)
U*P0137O2 sensor (HO2S) circuit low
voltage (Sensor-2)Output voltage of HO2S-2 is less than specification while
engine is idling after driving with high engine load and
Max. output voltage of HO2S-2 minus Min. output voltage
of HO2S-2 is less than specification.2 driving
cycles
)
U*P0138O2 sensor (HO2S) circuit high
voltage (Sensor-2)Output voltage of HO2S-2 is more than specification while
engine is idling after driving with high engine load and
Max. output voltage of HO2S-2 minus Min. output voltage
of HO2S-2 is less than specification.2 driving
cycles
)
U*P0140O2 sensor (HO2S) circuit no activity
detected (Sensor-2)Output voltage of HO2S-2 is more than specification after
warming up engine.
2 driving
cycles
)
U*P0171System too leanTotal fuel trim is larger than specification for specified time
or longer. (Fuel trim toward rich side is large.)2 driving
cycles
)
U*P0172System too richTotal fuel trim is smaller than specification for specified
time or longer. (Fuel trim toward lean side is large.)2 driving
cycles
) *P0222Throttle position sensor (sub) circuit
lowOutput voltage of throttle position sensor (sub) is lower
than specification.1 driving
cycle
) *P0223Throttle position sensor (sub) circuit
highOutput voltage of throttle position sensor (sub) is higher
than specification.1 driving
cycle
)
U*P0300Random misfire detected
Misfire of such level as to cause damage to three way
catalyst or misfire of such level as to deteriorate emission.*2 driving
cycles )U*P030
1 /
U*P0302 /
U*P0303 /
U*P0304Cylinder 1 misfire detected
Cylinder 2 misfire detected
Cylinder 3 misfire detected
Cylinder 4 misfire detected
) *P0327 Knock sensor circuit low Output voltage of knock sensor is less than specification.1 driving
cycle
) *P0328 Knock sensor circuit high Output voltage of knock sensor is more than specification.1 driving
cycle
) *P0335 Crankshaft position sensor circuitNo signal of CKP sensor for specified time even if starting
motor signal is input.1 driving
cycle
) *P0340 Camshaft position sensor circuit CMP sensor pulse is out of specification.1 driving
cycle
)
U*P0401Exhaust gas recirculation flow
detected as insufficientDifference in intake manifold absolute pressure between
opened EGR valve and closed EGR valve is less than
specification.2 driving
cycles
)
U*P0402Exhaust gas recirculation flow
detected as excessive
Difference in intake manifold absolute pressure between
opened EGR valve and closed EGR valve is more than
specification.2 driving
cycles
)
U*P0403Exhaust gas recirculation control
circuitOutput voltage is different from output command with
more than one pole out of 4 poles.1 driving
cycle DTC No. Detecting itemDetecting condition
(DTC will set when detecting:)MIL

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Scan Tool Data Definitions
COOLANT TEMP (ENGINE COOLANT
TEMPERATURE, °C, °F)
It is detected by engine coolant temp. sensor.
INTAKE AIR TEMP. (°C, °F)
It is detected by intake air temp. sensor.
ENGINE SPEED (rpm)
It is computed by reference pulses from the camshaft
position sensor.
DESIRED IDLE (DESIRED IDLE SPEED, rpm)
The Desired Idle Speed is an ECM internal parameter
which indicates the ECM requested idle. If the engine is
not running, this number is not valid.
MAF (MASS AIR FLOW RATE, g/s, lb/min.)
It represents total mass of air entering intake manifold
which is measured by mass air flow sensor.
CALC LOAD (CALCULATED LOAD VALUE, %)
Engine load displayed as a percentage of maximum
possible load. Value is calculated mathematically using
the formula: actual (current) intake air volume ÷
maximum possible intake air volume × 100%
MAP (MANIFOLD ABSOLUTE PRESSURE, in.Hg,
kPa)
This value indicates how much correction is necessary
to keep the air/fuel mixture stoichiometrical.
It is detected by manifold absolute pressure sensor.
THROTTLE POS (RELATIVE THROTTLE POSITION,
%)
When throttle position sensor is at fully closed position,
throttle opening is indicated as 0 – 12% and 90 – 100%
full open position.
BAROMETRIC PRESS (kPa, in.Hg)
This parameter represents a measurement of barometric
air pressure and is used for altitude correction of the fuel
injection quantity.
FUEL TANK LEVEL (%)
This parameter indicates approximate fuel level in fuel
tank. As detectable range of fuel level sensor is set as 0
to 100%, however, with some models whose fuel tank
capacity is smaller, indicated fuel level may be only 70%
even when fuel tank is full.
BATTERY VOLTAGE (V)
This parameter indicates battery positive voltage
inputted from main relay to ECM.
BRAKE SW (ON/OFF)
This parameter indicates the state of the brake switch.FUEL SYSTEM B1 (FUEL SYSTEM STATUS)
Air/fuel ratio feedback loop status displayed as one of
the followings.
OPEN: Open-loop has not yet satisfied conditions to go
closed loop.
CLOSED: Closed-loop using oxygen sensor(s) as
feedback for fuel control.
OPEN-DRIVE COND: Open-loop due to driving
conditions (Power enrichment, etc.).
OPEN SYS FAULT: Open-loop due to detected system
fault.
O2S SENSOR B1 S1 (HEATED OXYGEN SENSOR-1,
V)
It indicates output voltage of HO2S-1 installed on
exhaust manifold (pre-catalyst.)
O2S SENSOR B1 S2 (HEATED OXYGEN SENSOR-2,
V)
It indicates output voltage of HO2S-2 installed on
exhaust pipe (post-catalyst). It is used to detect catalyst
deterioration.
SHORT FT B1 (SHORT TERM FUEL TRIM, %)
Short term fuel trim value represents short term
corrections to the air/fuel mixture computation. A value
of 0 indicates no correction, a value greater than 0
means an enrichment correction, and a value less than 0
implies an enleanment correction.
LONG FT B1 (LONG TERM FUEL TRIM, %)
Long term fuel trim value represents long term
corrections to the air/fuel mixture computation. A value
of 0 indicates no correction, a value greater than 0
means an enrichment correction, and a value less than 0
implies an enleanment correction.
TOTAL FUEL TRIM B1 (%)
The value of Total Fuel Trim is obtained by calculating
based on values of Short Term Fuel Trim and Long Term
Fuel Trim. This value indicates how much correction is
necessary to keep the air/fuel mixture stoichiometrical.
FUEL CUT (ON/OFF)
ON: Fuel being cut (output signal to injector is stopped)
OFF: Fuel not being cut
O2S B1 S2 ACT (HEATED OXYGEN SENSOR-2,
ACTIVE / INACTIVE)
This parameter indicates activation condition of HO2S-2
ACTIVE: Activating
INACTIVE: warming up or at stop
O2S B1 S1 ACT (HEATED OXYGEN SENSOR-1,
ACTIVE / INACTIVE)
This parameter indicates activation condition of HO2S-1
ACTIVE: Activating
INACTIVE: warming up or at stop

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THROTTLE MOTOR RELAY (ON/OFF)
ON: Throttle actuator (motor) control activated by ECM.
OF: Throttle actuator (motor) control stopped by ECM.
VEHICLE SPEED (km/h, mph)
It is computed based on pulse signals from front wheel
speed sensor (RH, LH) (for M/T model) or output shaft
speed sensor (VSS) (for A/T model).INJ PULSE WIDTH (FUEL INJECTION PULSE WIDTH,
msec.)
This parameter indicates time of the injector drive (valve
opening) pulse which is output from ECM (but injector
drive time of NO.1 cylinder for multiport fuel injection).
Visual InspectionS6RW0D1104008
Visually check the following parts and systems.
Engine Basic InspectionS6RW0D1104009
This check is very important for troubleshooting when ECM has detected no DTC and no abnormality has been found
in “Visual Inspection”.
Follow the flow carefully.Inspection item Reference section
• Engine oil – level, leakage “Engine Oil and Filter Change in Section 0B”
• Engine coolant – level, leakage “Coolant 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 Dismounting and Remounting 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 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 “Generator Symptom Diagnosis in Section 1J”
• Engine oil pressure warning lamp – Operation “Oil Pressure Switch Inspection in Section 9C”
• Engine coolant temp. meter – Operation“Engine Coolant Temperature (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
Step Action Yes No
1Was “Engine and Emission Control System Check”
performed?Go to Step 2. Go to “Engine and
Emission Control
System Check”.
2Check battery voltage
Is it 11 V or more?Go to Step 3. Charge or replace
battery.
3Is vehicle equipped with keyless start control system?Go to Step 4. Go to Step 5.

Downloaded from www.Manualslib.com manuals search engine 1A-92 Engine General Information and Diagnosis:
DTC P0131 / P0132: O2 Sensor (HO2S) Circuit Low Voltage / High Voltage (Sensor-1)S6RW0D1104031
Wiring Diagram
DTC Detecting Condition and Trouble Area
E01C01
3 4
18 19 5 6 7 10 11
17 20
47 46 49 50 51 21 22
5216 259
24 14
29
55 57 54 53 59
60 582
26 27 28 15
30
56 4832 31 34 35 36 37 40 42 39 38 44
45 43 41 331 12 13
238 3 4
18 19 5 6 7 10 11
17 20
47 46 49 50 51 21 22
5216 259
24 14
29
55 57 54 53 59
60 582
26 27 28 15
30
56 4832 31 34 35 36 37 40 42 39 38 44
45 43 41 331 12 13
238
BLK/WHT
WHT
11
GRN
39
E01-29
WHT
ORN
BLK/WHT
BLKC01-46
C01-10
C01-57
6
7
10
BLK
BLUWHT
BLK/RED
1
4
5
8
12
I6RW0D110027-01
1. Main fuse box 4. Junction block assembly 7. Heater 10. To HO2S-2
2. Shield wire 5. “IG COIL” fuse 8. To HO2S-2 heater 11. Individual circuit fuse box No.1
3. Ignition switch 6. HO2S-1 9. ECM 12. “IGN” fuse
DTC detecting condition Trouble area
DTC P0131:
Maximum HO2S voltage is lower than specified voltage.
(2 driving cycle detection logic, monitoring once/1 driving)
DTC P0132:
Minimum HO2S voltage is higher than specified voltage.
(2 driving cycle detection logic, monitoring once/1 driving)• HO2S-1 circuit
•HO2S-1
• Fuel system
•ECM
• Fuel shortage
• Exhaust system
• Air intake system

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4HO2S-1 ground check
1) Disconnect connector from HO2S-1 with ignition switch
turned OFF.
2) Check for proper connection to HO2S-1 connector at
“BLK/RED”, “WHT”, “BLK/WHT” and “ORN” wire
terminals.
3) If connections are OK, measure resistance between
“ORN” wire terminal of HO2S-1 connector and engine
ground.
Is measured resistance less than 5
Ω?Go to Step 5. “ORN” wire is open or
high resistance circuit.
Poor “C01-57” terminal
connection. Faulty ECM
ground.
If they are OK,
substitute a known-
good ECM and recheck.
5Wire circuit check
1) Turn OFF ignition switch.
2) Remove ECM from its bracket with ECM connectors
connected.
3) Measure resistance between “WHT” wire terminal of
HO2S-1 connector and “C01-10” terminal of ECM
connector.
Is resistance less than 5
Ω?Go to Step 6. “WHT” wire is high
resistance circuit or
open circuit. Poor “C01-
10” terminal connection.
Faulty ECM ground. If
they are OK, substitute
a known-good ECM and
recheck.
6Wire circuit check
1) Disconnect connectors from ECM with ignition switch
turn OFF.
2) Measure resistance between “WHT” wire terminal of
HO2S-1 connector and vehicle body ground.
Is resistance infinity?Go to Step 7. “WHT” wire is shorted to
ground circuit.
7HO2S-1 signal circuit check
1) Measure voltage between “WHT” wire terminal of HO2S-
1 connector and vehicle body ground.
Is voltage 0 V?Go to Step 8. “WHT” wire is shorted to
other circuit.
8HO2S-1 heater circuit check
1) Check HO2S-1 heater circuit referring to “DTC P0031 /
P0032: HO2S Heater Control Circuit Low / High
(Sensor-1)”.
Is circuit in good condition?Go to Step 9. Repair HO2S-1 circuit.
9Exhaust system check
1) Check exhaust system for exhaust gas leakage.
Is it OK?Go to Step 4 in “DTC
P0171 / P0172: Fuel
System Too Lean /
Rich”.
If it is in good condition,
go to Step 10.Repair leakage of
exhaust system.
10Air intake system check
1) Check air intake system for clog or leak.
Is it OK?Replace HO2S-1
referring to “Heated
Oxygen Sensor (HO2S-
1 and HO2S-2)
Removal and
Installation (If Equipped)
in Section 1C”.
If DTC still exists,
substitute a known-
good ECM and recheck.Repair or replace air
intake system. Step Action Yes No

Downloaded from www.Manualslib.com manuals search engine 1A-96 Engine General Information and Diagnosis:
DTC P0134: O2 Sensor (HO2S) Circuit No Activity Detected (Sensor-1)S6RW0D1104033
Wiring Diagram
Refer to “DTC P0131 / P0132: O2 Sensor (HO2S) Circuit Low Voltage / High Voltage (Sensor-1)”.
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 are 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 temperature: 70 °C (158 °F) or more
• Altitude (barometric pressure): 2500 m, 8200 ft or less (560 mmHg, 74.4 kPa or more)

1) With ignition switch turned OFF, connect scan tool.
2) Turn ON ignition switch and clear DTC using scan tool.
3) Start engine and warm up to normal operating temperature.
4) Drive vehicle at 40 mph (60 km/h) or higher. (engine speed: 2500 – 3000 r/min.)
5) Keep above vehicle speed for 6 min. or more. (Throttle valve opening is kept constant in this step.)
6) Release accelerator pedal and with engine brake applied, keep vehicle coasting (with fuel cut for 3 sec. or more)
and then stop vehicle.
7) Check DTC and pending DTC.
DTC Troubleshooting
NOTE
Before this troubleshooting is performed, read the precautions for DTC troubleshooting referring to
“Precautions for DTC Troubleshooting”.

DTC detecting condition Trouble area
HO2S voltage is higher than specified value for 1 min. after warming up engine or
HO2S voltage is lower than specified value for 1 min. after warming up engine.
(2 driving cycle detection logic)•HO2S-1
• HO2S-1 circuit
• Exhaust gas leakage
•ECM
• Air intake system
Step Action Yes No
1Was “Engine and Emission Control System Check”
performed?Go to Step 2. Go to “Engine and
Emission Control
System Check”.

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2HO2S-1 output voltage check
1) Connect scan tool to DLC with ignition switch turned
OFF.
2) Warm up engine to normal operating temperature and
keep it at 2000 r/min. for 60 sec.
3) Repeat racing engine (Repeat depressing accelerator
pedal 5 to 6 times continuously to enrich A/F mixture and
take foot off from pedal to enlean it) and check HO2S
output voltages displayed on scan tool.
Is over 0.6 V and below 0.3 V indicated?Intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection
Inspection in Section
00”. If check result is
OK, go to Step 3.Go to Step 3.
3HO2S-1 ground check
1) Disconnect connector from HO2S-1 with ignition switch
turned OFF.
2) Check for proper connection to HO2S-1 at “BLK/RED”,
“WHT”, “BLK/WHT” and “ORN” wire terminals.
3) If wire and connection are OK, measure resistance
between “ORN” wire terminal of HO2S-1 connector and
engine ground.
Is resistance less than 5
Ω?Go to Step 4. “ORN” wire is open or
high resistance circuit.
Poor “C01-57” terminal
connection. Faulty ECM
ground.
If they are OK,
substitute a known-
good ECM and recheck.
4Wire circuit check
1) Turn OFF ignition switch.
2) Remove ECM from its bracket with ECM connectors
connected.
3) Measure resistance between “WHT” wire terminal of
HO2S-1 connector and “C01-10” terminal of ECM
connector.
Is resistance less than 5
Ω?Go to Step 5. “WHT” wire is high
resistance circuit or
open circuit. Poor “C01-
10” terminal connection
of ECM connector.
Faulty ECM ground. If
they are OK, substitute
a known-good ECM and
recheck.
5Wire circuit check
1) Disconnect connectors from ECM with ignition switch
turned OFF.
2) Measure resistance between “WHT” wire terminal of
HO2S-1 connector and vehicle body ground.
Is resistance infinity?Go to Step 6. “WHT” wire is shorted to
ground circuit.
6HO2S-1 heater circuit check
1) Check HO2S-1 heater circuit referring to “DTC P0031 /
P0032: HO2S Heater Control Circuit Low / High
(Sensor-1)”.
Is it in good condition?Go to Step 7. Repair HO2S-1 circuit.
7Exhaust system check
1) Check exhaust system for exhaust gas leakage.
Is it OK?Go to Step 4 in “DTC
P0171 / P0172: Fuel
System Too Lean /
Rich”.
If it is in good condition,
go to Step 8.Repair leakage of
exhaust system. Step Action Yes No

Downloaded from www.Manualslib.com manuals search engine 1A-98 Engine General Information and Diagnosis:
DTC P0137 / P0138: O2 Sensor (HO2S) Circuit Low Voltage / High Voltage (Sensor-2)S6RW0D1104034
Wiring Diagram
DTC Detecting Condition and Trouble Area8Air intake system check
1) Check air intake system for clog or leak.
Is it OK?Replace HO2S-1
referring to “Heated
Oxygen Sensor (HO2S-
1 and HO2S-2)
Removal and
Installation (If Equipped)
in Section 1C”.
If DTC still exists,
substitute a known-
good ECM and recheck.Repair or replace air
intake system. Step Action Yes No
E01C01
3 4
18 19 5 6 7 10 11
17 20
47 46 49 50 51 21 22
5216 259
24 14
29
55 57 54 53 59
60 582
26 27 28 15
30
56 4832 31 34 35 36 37 40 42 39 38 44
45 43 41 331 12 13
238 3 4
18 19 5 6 7 10 11
17 20
47 46 49 50 51 21 22
5216 259
24 14
29
55 57 54 53 59
60 582
26 27 28 15
30
56 4832 31 34 35 36 37 40 42 39 38 44
45 43 41 331 12 13
238
BLK/WHT
WHT
11
GRN
39
E01-29
BRN
ORN
BLK/WHT
BLKC01-47
C01-11
C01-57
6
2 7
10
BLK
BLUWHT
RED/BLU
1
4
5
8
12
5V
I6RW0D110028-01
1. Main fuse box 4. Junction block assembly 7. Heater 10. To HO2S-1
2. Shield wire 5. “IG COIL” fuse 8. To HO2S-1 heater 11. Individual circuit fuse box No.1
3. Ignition switch 6. HO2S-2 9. ECM 12. “IG ACC” fuse
DTC detecting condition Trouble area
DTC P0137:
HO2S-2 voltage is lower than specified value while engine is idling after driving with
high engine load (high speed) for specified time. And HO2S-2 max. voltage minus
HO2S-2 min. voltage is less than specified value for 40 sec.
(2 driving cycle detection logic)
DTC P0138:
HO2S-2 voltage is higher than specified value while engine is idling after driving with
high engine load (high speed) for specified time. And HO2S-2 max. voltage minus
HO2S-2 min. voltage is less than specified value for 40 sec.
(2 driving cycle detection logic)•HO2S-2
• HO2S-2 circuit
• Fuel system
•ECM
• Fuel shortage
• Exhaust system
• Air intake system