1A-9 SUZUKI SWIFT 2008 2.G Service Workshop Manual

Downloaded from www.Manualslib.com manuals search engine Table of Contents 1- i
1
Section 1
CONTENTS
Engine
Precautions ................................................. 1-1
Precautions............................................................. 1-1
Precautions for Engine .......................................... 1-1
Engine General Information and
Diagnosis ............. .................................... 1A-1
Precautions........................................................... 1A-1
Precautions on Engine Service ........................... 1A-1
Precaution on On-Board Diagnostic (OBD) System .............................................................. 1A-1
Precautions in Diagnosing Trouble ..................... 1A-1
Precautions of ECM Circuit Inspection................ 1A-2
Precautions of Electric Throttle Body System
Calibration ......................................................... 1A-2
General Description ............................................. 1A-2 Statement on Cleanliness and Care ................... 1A-2
Engine Diagnosis General Description ............... 1A-3
On-Board Diagnostic System Description ........... 1A-3
Data Link Connector (DLC) ................................. 1A-6
Engine and Emission Control System Description ........................................................ 1A-6
CAN Communication System Description........... 1A-7
Air Intake System Description ............................. 1A-9
Description of Electric Throttle Body System ...... 1A-9
Description of Electric Throttle Body System Calibration ....................................................... 1A-10
Fuel Cut Control Description ............................. 1A-10
Generator Control System Description ............. 1A-11
Electronic Control System Description .............. 1A-12
Engine and Emission Control Input / Output Table ............................................................... 1A-18
Schematic and Routing Diagram ...................... 1A-19 Engine and Emission Control System Diagram .......................................................... 1A-19
Component Locatio n ......................................... 1A-21
Electronic Control System Components Location .......................................................... 1A-21
Diagnostic Information and Procedures .......... 1A-22 Engine and Emission Control System Check.... 1A-22
Malfunction Indicator Lamp (MIL) Check .......... 1A-25
DTC Check ....................................................... 1A-26
DTC Clearance ................................................. 1A-27
DTC Table ......................................................... 1A-27
Fail-Safe Table ................ .................................. 1A-31 Scan Tool Data ................................................. 1A-33
Visual Inspection ............................................... 1A-37
Engine Basic Inspection .................................... 1A-38
Engine Symptom Diagnosis .............................. 1A-41
MIL Does Not Come ON with Ignition Switch
ON and Engine Stop (but Engine Can Be
Started) ........................................................... 1A-47
Malfunction Indicator Lamp Remains ON after Engine Starts................................................... 1A-48
DTC P0010: “A” Camshaft Position Actuator Circuit .............................................................. 1A-49
DTC P0011 / P0012: “A” Camshaft Position - Timing Over-Advanced or System
Performance / -Retarded................................. 1A-52
DTC P0031 / P0032: HO2S Heater Control Circuit Low / High (Sensor-1) .......................... 1A-54
DTC P0037 / P0038: HO2S Heater Control Circuit Low / High (Sensor-2) .......................... 1A-56
DTC P0101: Mass or Volume Air Flow Circuit Range / Performance ...................................... 1A-58
DTC P0102: Mass or Volume Air Flow Circuit Low Input......................................................... 1A-61
DTC P0103: Mass or Volume Air Flow Circuit High Input ........................................................ 1A-63
DTC P0106: Manifold Absolute Pressure /
Barometric Pressure Circuit Range /
Performance.................................................... 1A-64
DTC P0107: Manifold Absolute Pressure /
Barometric Pressure Circ uit Low Input............ 1A-66
DTC P0108: Manifold Absolute Pressure /
Barometric Pressure Circ uit High Input ........... 1A-67
DTC P0111: Intake Air Temperature Sensor 1 Circuit Range / Performance ........................... 1A-69
DTC P0112: Intake Air Temperature Sensor 1 Circuit Low ...................................................... 1A-72
DTC P0113: Intake Air Temperature 1 Sensor Circuit High...................................................... 1A-74
DTC P0116: Engine Coolant Temperature Circuit Range / Performance ........................... 1A-76
DTC P0117: Engine Coolant Temperature Circuit Low ...................................................... 1A-79
DTC P0118: Engine Coolant Temperature Circuit High...................................................... 1A-81
DTC P0122: Throttle / Pedal Position Sensor / Switch “A” (Main) Circuit Low ........................ 1A-83

Downloaded from www.Manualslib.com manuals search engine 1-ii Table of Contents
DTC P0123: Throttle / Pedal Position Sensor / Switch “A” (Main) Circuit High ....................... 1A-85
DTC P0131 / P0132: O2 Sensor (HO2S) Circuit Low Voltage / High Voltage (Sensor-
1) ..................................................................... 1A-88
DTC P0133: O2 Sensor (HO2S) Circuit Slow
Response (Sensor- 1) ...................................... 1A-91
DTC P0134: O2 Sensor (HO2S) Circuit No Activity Detected (Sensor -1) ........................... 1A-92
DTC P0137 / P0138: O2 Sensor (HO2S) Circuit Low Voltage / High Voltage (Sensor-
2) ..................................................................... 1A-94
DTC P0140: O2 Sensor (HO2S) Circuit No Activity Detected (Sensor -2) ........................... 1A-97
DTC P0171 / P0172: Fuel System Too Lean / Rich ................................................................. 1A-98
DTC P0222: Throttle / Pedal Position Sensor / Switch “B” (Sub) Circuit Low ....................... 1A-100
DTC P0223: Throttle / Pedal Position Sensor / Switch “B” (Sub) Circuit High ...................... 1A-102
DTC P0300 / P0301 / P0302 / P0303 / P0304: Random / Multiple Cylin der Misfire Detected
/ Cylinder 1 / Cylinder 2 / Cylinder 3 /
Cylinder 4 Misfire Detected ........................... 1A-105
DTC P0327 / P0328: Knoc k Sensor 1 Circuit
Low / High ..................................................... 1A-107
DTC P0335: Crankshaft Position (CKP) Sensor “A” Circuit .......................................... 1A-109
DTC P0340: Camshaft Position (CMP) Sensor “A” Circuit .......................................... 1A-111
DTC P0350: Ignition Coil Primary / Secondary Circuit ............................................................ 1A-114
DTC P0401 / P0402: Exhaust Gas Recirculation Flow Insufficient Detected /
Excessive Detected ...................................... 1A-116
DTC P0403: Exhaust Gas Recirculation Control Circuit ................... ............................ 1A-118
DTC P0420: Catalyst System Efficiency
below Threshold ................ ............................ 1A-120
DTC P0443: Evaporativ e Emission System
Purge Control Valve Circuit ........................... 1A-122
DTC P0480: Fan 1 (Radiator Cooling Fan) Control Circuit ................... ............................ 1A-124
DTC P0500: Vehicle Speed Sensor “A” Malfunction .................................................... 1A-128
DTC P0532: A/C Refrigerant Pressure Sensor “A” Circuit Low ... ............................... 1A-130
DTC P0533: A/C Refrigerant Pressure Sensor “A” Circuit High ................................. 1A-132
DTC P0601 / P0602 / P0607: Internal Control Module Memory Check Sum Error / Control
Module Programming Error / Control Module
Performance ................................................. 1A-134
DTC P0616: Starter Relay Circuit Low............ 1A-135
DTC P0617: Starter Relay Circuit High ........... 1A-136
DTC P0620: Generator Control Circuit ........... 1A-137
DTC P0625 / P0626: Generator Field Terminal Circuit Low / High . .......................... 1A-139
DTC P1501 / P1502: Electric Load Current Sensor Circuit Low / High . ............................ 1A-141 DTC P1510: ECM Back-Up Power Supply
Malfunction .................................................... 1A-143
DTC P1603: TCM Trouble Code Detected ..... 1A-144
DTC P1674: CAN Communication (Bus Off Error) ............................................................. 1A-145
DTC P1676: CAN Communication (Reception Error for TCM) ............................................... 1A-148
DTC P1678: CAN Communication (Reception Error for BCM) ............................................... 1A-149
DTC P1685: CAN Communication (Reception Error for ABS/ESP ® Control Module) ........... 1A-150
DTC P2101: Throttle Actuator Control Motor Circuit Range / Performance ......................... 1A-152
DTC P2102: Throttle Actuator Control Motor Circuit Low .................................................... 1A-154
DTC P2103: Throttle Actuator Control Motor Circuit High.................................................... 1A-155
DTC P2111 / P2112: Throttle Actuator Control System - Stuck Open / Closed ...................... 1A-156
DTC P2119: Throttle Actu ator Control Throttle
Body Range / Performance ........................... 1A-157
DTC P2122: Throttle / Pedal Position Sensor / Switch “D” (Main) Circuit Low Input............. 1A-159
DTC P2123: Throttle / Pedal Position Sensor / Switch “D” (Main) Circuit High Input ............ 1A-161
DTC P2127: Throttle Pedal Position Sensor / Switch “E” (Sub) Circuit Low Input ................ 1A-164
DTC P2128: Throttle / Pedal Position Sensor
/ Switc
h “E” (Sub) Circuit High Input ............. 1A-166
DTC P2135: Throttle / Pedal Position Sensor / Switch “A”/“B” (Main / Sub) Voltage
Correlation..................................................... 1A-168
DTC P2138: Throttle / Pedal Position Sensor / Switch “D”/“E” (Main / Sub) Voltage
Correlation..................................................... 1A-171
DTC P2227 / P2228 / P2229: Barometric Pressure Circuit Malfunction ......................... 1A-173
Inspection of ECM and Its Circuits .................. 1A-175
ECM Power and Ground Circuit Check........... 1A-194
Fuel Injector Circuit Check .............................. 1A-198
Fuel Pump and Its Circuit Check..................... 1A-200
Fuel Pressure Check....................................... 1A-203
A/C System Circuits Check ............................. 1A-205
Electric Load Signal Circuit Check .................. 1A-209
Radiator Cooling Fan Low Speed Control System Check ............................................... 1A-211
Radiator Cooling Fan High Speed Control System Check ............................................... 1A-213
Repair Instructions ......... .................................1A-216
Idle Speed and IAC Throttle Valve Opening Inspection ...................................................... 1A-216
Special Tools and Equipmen t .........................1A-217
Special Tool .................................................... 1A-217
Aux. Emission Control Devices ............. 1B-1
Diagnostic Information and Procedures ............1B-1
EGR System Inspection ...................................... 1B-1
Repair Instructions ............ ..................................1B-1
EVAP Canister Purge Inspec tion ........................ 1B-1

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Air Intake System DescriptionS7RS0B1101006
The main components of the air intake system are air cleaner (1), air cleaner outlet hose (2), electric throttle body (3)
(for the details, refer to “Description of Electric Throttle Body System”.), and intake manifold (4).
The air (by the amount corresponding to throttle valve (5) opening and engine speed) is filtered by the air cleaner,
distributed by the intake, and finally drawn into each combusti on chamber. Electric throttle body is not equipped with
IAC valve for idle speed control. Idle speed control is done by the throttle actuator (6) which opens/closes the throttle
valve. (For the details, refer to “Description of Electric Throttle Body System”).
Description of Electric Throttle Body SystemS7RS0B1101007
The Electric Throttle Body System consists of electric throttle body asse mbly, APP sensor assembly, ECM and throttle
actuator control relay.
Among them, assembly components are as follows.
• Electric throttle body assembly: throttle valve, throttle actuator, 2 throttle position sensors
• APP sensor assembly: Accelerator pe dal, 2 accelerator position sensors
Operation Description
ECM (5) detects opening (depressed extent of pedal) of the accelerator pedal based on signal voltage of the APP
sensor (1) and using that data and engi ne operation condition, it calculates the optimum throttle valve opening. On the
other hand, it detects the throttle valve opening based on the signal voltage of the throttle position sensor (3) included
in the throttle body (2) and compares it with above calculated optimum throttle valve opening. When there is a
difference between them, ECM controls the duty ratio (100% – 0%) according to this difference to drive the throttle
actuator (motor) (4) included in the throttle body. When th ere is no difference, ECM controls the duty ratio to about
15% to maintain the throttle valve opening . In this way, the throttle valve (17) is opened and closed to achieve the
optimum throttle valve opening.
In this system, as the thrott le position sensor and APP sensor have 2 sensors (main and sub) each, highly accurate
and highly reliable control and abnormality detection are assured. Also, when ECM detects an abnormality in the
system, it turns off the th rottle actuator control relay (8) to step controlling the throttle actuator.
When the throttle actuator control relay is turned off, the throttle valve is fixed at the specified opening below from its
completely closed position (default openin g) by the force of the return spring and open spring included in the throttle
body.
This throttle body is not equipped with IAC valve for idle speed control. Idle speed control is done by the throttle
actuator which opens/closes the throttle valve.
4 2
1
3
5
6
I5RW0A110006-02

Downloaded from www.Manualslib.com manuals search engine 1A-90 Engine General Information and Diagnosis:
4HO2S-1 ground check
1) Disconnect connector from HO 2S-1 with ignition switch
turned OFF.
2) Check for proper connection to HO2S-1 connector at “BLK/RED”, “WHT”, “BLK /WHT” and “YEL” wire
terminals.
3) If connections are OK, m easure resistance between
“YEL” wire terminal of HO2S-1 connector and engine
ground.
Is measured resistance less than 5
Ω? Go to Step 5. “YEL” wire is open or
high resistance circuit.
Poor “C37-57” terminal
connection. Faulty ECM
ground.
If they are OK,
substitute a known-
good ECM and recheck.
5 Wire circuit check
1) Turn OFF ignition switch.
2) Remove ECM from its br acket with ECM connectors
connected.
3) Measure resistance between “WHT” wire terminal of HO2S-1 connector and “C37-10” terminal of ECM
connector.
Is resistance less than 5
Ω? Go to Step 6. “WHT” wire is high
resistance circuit or
open circuit. Poor “C37-
10” terminal connection.
Faulty ECM ground. If
they are OK, substitute
a known-good ECM and
recheck.
6 Wire 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.
7 HO2S-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.
8 HO2S-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.
9 Exhaust 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.
10 Air intake system check
1) Check air intake system for clog or leak.
Is it OK? Check HO2S-1 referring
to “HO2S-1 and HO2S-
2 Heater On-Vehicle
Inspection in Section
1C”.
If it is in good condition,
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 Engine General Information and Diagnosis: 1A-91
DTC P0133: O2 Sensor (HO2S) Circuit Slow Response (Sensor-1)S7RS0B1104032
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 temperature: 70 °C (158 °F) to 150 °C (302 °F)
• Altitude (barometric pressure): 2400 m, 8000 ft or less (560 mmHg, 75 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. (Throt tle 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 if DTC and pending DTC exist by using scan tool. If not, check if oxygen sensor monitoring test has been
completed by using scan tool. If not in both of above c hecks (i.e., no DTC and pending DTC and oxygen sensor
monitoring test not completed), check vehicle cond ition (environmental) and repeat Step 3) through 6).
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 time (time to change from lean to rich or from rich to lean) of HO2S-1 output
voltage is about 1 sec. at minimum or aver age time of 1 cycle is 5 sec. at minimum.
(*2 driving cycle detection logic, monitoring once per driving cycle) Heated oxygen sensor-1
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 HO2S-1 (DTC P0133)? Go to applicable DTC
diag. flow.Replace HO2S-1.

Downloaded from www.Manualslib.com manuals search engine 1A-92 Engine General Information and Diagnosis:
DTC P0134: O2 Sensor (HO2S) Circuit No Activity Detected (Sensor-1)S7RS0B1104033
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 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 temperature: 70 °C (158 °F) to 150 °C (302 ° F)
• Altitude (barometric pressure): 2400 m, 8000 ft or less (560 mmHg, 75 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. (Throt tle 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 if DTC and pending DTC exist by using scan tool. If not, check if oxygen sensor monitoring test has been
completed by using scan tool. If not in both of above c hecks (i.e., no DTC and pending DTC and oxygen sensor
monitoring test not completed), check vehicle cond ition (environmental) and repeat Step 3) through 6).
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
HO2S voltage is higher than 0.6 V for more than 1 min
continuously after warming up engine or HO2S voltage is lower
than 0.3 V for more than 1 min continuously after warming up
engine.
(2 driving cycle detection logic) •HO2S-1
• HO2S-1 circuit
• Exhaust gas leakage
•ECM
• Air intake system
Step
Action YesNo
1 Was “Engine and Emission Control System Check”
performed? Go to Step 2.
Go to “Engine and
Emission Control
System Check”.

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-93
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 continuous ly 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.
3 HO2S-1 ground check
1) Disconnect connector from HO 2S-1 with ignition switch
turned OFF.
2) Check for proper connection to HO2S-1 at “BLK/RED”, “WHT”, “BLK/WHT” and “YEL” wire terminals.
3) If wire and connection are OK, measure resistance between “YEL” wire terminal of HO2S-1 connector and
engine ground.
Is resistance less than 5
Ω? Go to Step 4. “YEL” wire is open or
high resistance circuit.
Poor “C37-57” terminal
connection. Faulty ECM
ground.
If they are OK,
substitute a known-
good ECM and recheck.
4 Wire circuit check
1) Turn OFF ignition switch.
2) Remove ECM from its br acket with ECM connectors
connected.
3) Measure resistance between “WHT” wire terminal of HO2S-1 connector and “C37-10” terminal of ECM
connector.
Is resistance less than 5
Ω? Go to Step 5. “WHT” wire is high
resistance circuit or
open circuit. Poor “C37-
10” terminal connection
of ECM connector.
Faulty ECM ground. If
they are OK, substitute
a known-good ECM and
recheck.
5 Wire 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.
6 HO2S-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.
7 Exhaust 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.
8 Air intake system check
1) Check air intake system for clog or leak.
Is it OK? Check HO2S-1 referring
to “HO2S-1 and HO2S-
2 Heater On-Vehicle
Inspection in Section
1C”.
If it is in good condition,
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-94 Engine General Information and Diagnosis:
DTC P0137 / P0138: O2 Sensor (HO2S) Circuit Low Voltage / High Voltage (Sensor-2)S7RS0B1104034
Wiring Diagram
DTC Detecting Condition and Trouble Area
E23C37
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
BLK/WHT
WHT
11
GRN
3 9
E23-29
BRN
YEL
BLK/WHT
BLKC37-47
C37-11
C37-57
6
2
7
10
BLK
BLUWHT
RED/BLU
1
4
5
8
12
5V
I6RS0C110007-01
1. Main fuse box 4. Junction block assembly 7. Heater 10. To HO2S-1
2. Shield wire 5. “IG COIL” fuse8. To HO2S-1 heater 11. Individual circuit fuse box No.1
3. Ignition switch 6. HO2S-29. ECM 12. “IG ACC” fuse
DTC detecting condition Trouble area
DTC P0137:
HO2S-2 voltage is lower th an 0.4 V 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 0.1 V for 40 sec continuously.
(2 driving cycle detection logic)
DTC P0138:
HO2S-2 voltage is higher than 0.95 V 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 0.1 V for 40 sec
continuously.
(2 driving cycle detection logic) •HO2S-2
• HO2S-2 circuit
• Fuel system
•ECM
• Fuel shortage
• Exhaust system
• Air intake system

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-95
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 temperature: 70 °C (158 °F) to 150 °C (302 °F)
• Altitude (barometric pressure): 2400 m, 8000 ft or less (560 mmHg, 75 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) Increase vehicle speed to 70 – 80 km/h (43 – 50 mile/h) at 5th gear or D range.
5) Release accelerator pedal and with engine brake applied, ke ep vehicle coasting (with fuel cut for 4 sec. or more),
then stop vehicle and run engine at idle speed for 60 sec. or more.
6) Repeat Step 4).
7) Keep above vehicle speed for 8 min. or more. (Throt tle valve opening is kept constant in this step.)
8) Repeat Step 5).
9) 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)
and HO2S-2 (DTC P0140)? Go to applicable DTC
diag. flow.Go to Step 3.
3 HO2S-2 and its circuit 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 continuous ly to enrich A/F mixture and
take foot off from pedal to enlean it).
Does HO2S-2 output voltage indicate deflection between
over 0.35 V and below 0.25 V? Go to “DTC P0171 /
P0172: Fuel System
Too Lean / Rich”.
Go to Step 4.

Downloaded from www.Manualslib.com manuals search engine 1A-96 Engine General Information and Diagnosis:
4HO2S-2 ground check
1) Disconnect connector from HO 2S-2 with ignition switch
turned OFF.
2) Check for proper connection to HO2S-2 connector at “RED/BLU”, “BRN”, “YEL” and “BLK/WHT” wire
terminals.
3) If connections are OK, m easure resistance between
“YEL” wire terminal of HO2S-2 connector and engine
ground.
Is resistance less than 5
Ω? Go to Step 5. “YEL” wire is open or
high resistance circuit.
Poor “C37-57” terminal
connection. Faulty ECM
ground.
If they are OK,
substitute a known-
good ECM and recheck.
5 Wire circuit check
1) Turn OFF ignition switch.
2) Remove ECM from its br acket with ECM connectors
connected.
3) Measure resistance between “BRN” wire terminal of HO2S-2 connector and “C37-11” terminal of ECM
connector.
Is resistance less than 5
Ω? Go to Step 6. “BRN” wire is high
resistance circuit or
open circuit. Poor “C37-
11” terminal connection.
If they are OK,
substitute a known-
good ECM and recheck.
6 Wire circuit check
1) Disconnect connectors from ECM with ignition switch
turned OFF.
2) Measure resistance between “BRN” wire terminal of HO2S-2 connector and vehicle body ground.
Is resistance infinity? Go to Step 7. “BRN” wire is shorted to
ground circuit.
7 HO2S-2 signal circuit check
1) Measure voltage between “BRN” wire terminal of HO2S-
2 connector and vehicle body ground.
Is voltage 0 V? Go to Step 8. “BRN” wire is shorted to
other circuit.
8 HO2S-2 heater circuit check
1) Check HO2S-2 heater circuit referring to “DTC P0037 /
P0038: HO2S Heater Control Circuit Low / High
(Sensor-2)”.
Is circuit in good condition? Go to Step 9. Repair HO2S-2 circuit.
9 Exhaust 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.
10 Air intake system check
1) Check air intake system for clog or leak.
Is it OK? Check HO2S-2 referring
to “HO2S-1 and HO2S-
2 Heater On-Vehicle
Inspection in Section
1C”.
If it is in good condition,
substitute a known-
good ECM and recheck.Repair or replace air
intake system.
Step Action Yes No