troubleshooting SUZUKI SWIFT 2008 2.G Service User Guide

Downloaded from www.Manualslib.com manuals search engine 1A-56 Engine General Information and Diagnosis:
DTC P0037 / P0038: HO2S Heater Control Circuit Low / High (Sensor-2)S7RS0B1104016
Wiring Diagram
DTC Detecting Condition and Trouble Area
DTC Confirmation Procedure1) 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) Run engine at idle speed for 1 min.
5) 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.

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
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
HO2S-2 heater voltage is more than specified value or less than
specified value for 5 seconds continuously
(2 driving cycle detection logic) • HO2S-2 heater
• HO2S-2 heater circuit
•ECM

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-59
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 the 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) 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. (ECT approx. 90 – 95 °C, 194 – 203 °F)
4) Drive vehicle with engine speed: more than 2500 rpm for 1 min.
5) Increase vehicle speed to 80 km/h (45 mile/h) at 5th gear or D range.
6) Release accelerator pedal to decrease vehicle speed to 40 km/h (25 mile/h).
7) Stop vehicle and run it idle for 1 min.
8) 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 Visual inspection
Check MAF sensor and air intake system for:
• Objects which block measuring duct and resistor of MAF
sensor.
• Other air flow which does not pass the MAF sensor.
Are they in good condition? Go to Step 3.
Repair or replace.
3 MAF sensor and its circuit check
1) With ignition switch turned OFF, connect scan tool.
2) Start engine and warm up to normal operation
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 11. Go to Step 4.

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-61
DTC P0102: Mass or Volume Air Flow Circuit Low InputS7RS0B1104018
Wiring Diagram
Refer to “DTC P0101: Mass or Volume Air Flow Circuit Range / Performance”.
DTC Detecting Condition and Trouble Area
DTC Confirmation Procedure1) With ignition switch turned OFF, connect scan tool.
2) Turn ON ignition switch and clear DTC using scan tool.
3) Start engine and run it for 10 sec.
4) Check 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.

10 MAF sensor signal circuit check
1) Measure resistance between “GRN/BLK” wire terminal
of MAF and IAT sensor connector and “C37-26” terminal
of ECM connector.
Is resistance below 3
Ω? Faulty MAF and IAT
sensor.
“GRN/BLK” wire is open
or high resistance
circuit.
11 Is DTC P2135 detected? Go to “DTC P2135:
Throttle / Pedal Position
Sensor / Switch “A”/“B”
(Main / Sub) Voltage
Correlation”.Go to Step 12.
12 Is DTC P0106 displayed? Go to “DTC P0106:
Manifold Absolute
Pressure / Barometric
Pressure Circuit Range
/ Performance”.Substitute a known-
good ECM and recheck.
Step
Action YesNo
DTC detecting condition Trouble area
MAF sensor output voltage is less than 0.15 V for 0.5
seconds continuously
(1 driving cycle detection logic) • Open or short in MAF sensor circuit
• MAF sensor
•ECM
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 MAF sensor and its circuit check
1) Connect scan tool to DLC with ignition switch turned
OFF.
2) Start engine and check MAF value displayed on scan tool. (Refer to “Scan Tool Data” for normal value.)
Is normal value indicated? Intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection
Inspection in Section
00”.
Go to Step 3.

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-63
DTC P0103: Mass or Volume Air Flow Circuit High InputS7RS0B1104019
Wiring Diagram
Refer to “DTC P0101: Mass or Volume Air Flow Circuit Range / Performance”.
DTC Detecting Condition and Trouble Area
DTC Confirmation Procedure1) With ignition switch turned OFF, connect scan tool.
2) Turn ON ignition switch and clear DTC using scan tool.
3) Start engine and run it for 10 sec.
4) Check 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.

DTC detecting condition Trouble area
MAF sensor output voltage is higher than 4.85 V for 0.5 seconds
continuously.
(1 driving cycle detection logic) • Open or short in MAF sensor circuit
• MAF sensor
•ECM
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 MAF sensor and its circuit check
1) Connect scan tool to DLC with ignition switch turned
OFF.
2) Start engine and check MAF value displayed on scan tool. (Refer to “Scan Tool Data” for normal value.)
Is normal value indicated? Intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection
Inspection in Section
00”.
Go to Step 3.
3 MAF sensor power supply voltage check
1) Disconnect connector from MAF and IAT sensor with
ignition switch tuned OFF.
2) Turn ON ignition switch, measure voltage between engine ground and “BLK/RED” wire terminal of MAF and
IAT sensor connector.
Is voltage 10 – 14 V? Go to Step 4.
“BLK/RED” wire is open
circuit.
4 MAF sensor ground circuit check
1) Turn OFF ignition switch, measure resistance between
“GRY” wire terminal of MAF and IAT sensor connector
and engine ground.
Is resistance below 5
Ω? Go to Step 6. Go to Step 5.
5 Ground circuit check
1) Remove ECM from its br acket with ECM connectors
connected.
2) Measure resistance between “C37-27” terminal of ECM connector and engine ground.
Is resistance below 5
Ω? “GRY” wire is open or
high resistance circuit.
ECM grounds “E23-31”,
“C37-58”, “C37-15” and/
or “C37-30” circuit are
open or high resistance.
If wires are OK,
substitute a known-
good ECM and recheck.

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-65
DTC Confirmation Procedure
NOTE
Check to make sure that the 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) to 150 °C (302 °F)
• Altitude (barometric pressure): 2400 m, 8000 ft or less (560 mmHg, 75 kPa or more)

1) Connect scan tool to DLC with ignition switch OFF.
2) Turn ON ignition switch and clear DTC using scan tool and warm up engine completely.
3) Increase engine speed up to 2000 rpm or more for 10 seconds.
4) Run engine at idle speed for 1 min.
5) 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 MAP sensor and its circuit check
1) Connect scan tool to DLC with ignition switch turned
OFF.
2) Turn ON ignition switch.
3) Check DTC.
Is there DTC P0107 or DTC P0108? Go to applicable DTC
diag. flow.
Go to Step 3.
3 MAP sensor output signal check
1) Check MAP sensor acco rding to “MAP Sensor
Inspection in Section 1C”.
Is it in good condition? Go to Step 4.
Faulty MAP sensor.
4 MAP sensor circuit check
1) Check MAP sensor circuit referring to Step 3 to 6 of
“DTC P0107: Manifold Absolute Pressure / Barometric
Pressure Circuit Low Input” or Step 3 to 8 of “DTC
P0108: Manifold Absolute Pressure / Barometric
Pressure Circuit High Input”.
Is circuit in good condition? Go to Step 5.
Repair or replace.
5 Air intake system check
1) Check air intake system for clog or leak.
Is it in good condition? Substitute a known-
good ECM and recheck.
Repair or replace.

Downloaded from www.Manualslib.com manuals search engine 1A-66 Engine General Information and Diagnosis:
DTC P0107: Manifold Absolute Pressure / Barometric Pressure Circuit Low InputS7RS0B1104021
Wiring Diagram
Refer to “DTC P0106: Manifold Absolute Pressure / Barometric Pressure Circuit Range / Performance”
DTC Detecting Condition and Trouble Area
DTC Confirmation Procedure 1) Connect scan tool to DLC with ignition switch turned OFF.
2) Turn ON ignition switch and clear DTC using scan tool.
3) Run engine at idle speed for 1 min.
4) Check 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.

DTC detecting condition Trouble area
Manifold absolute pressure se nsor output voltage is lower
than specified value for s pecified time continuously.
(1 driving cycle detection logic) • Manifold absolute pressure sensor circuit
• Manifold absolute pressure sensor
• A/C refrigerant pressure sensor (if equipped with A/C)
•ECM
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 MAP sensor and its circuit check
1) Connect scan tool to DLC with ignition switch turned
OFF.
2) Turn ON ignition switch.
3) Check intake manifold pressure displayed on scan tool.
Is it 0 kPa (0 in.Hg)? Go to Step 3.
Intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection
Inspection in Section
00”.
3 MAP sensor power supply voltage check
1) Disconnect connector from MAP sensor with ignition
switch turned OFF.
2) Check for proper connection of MAP sensor at “GRY/ RED”, “RED/BLK” and “ORN” wire terminals.
3) Turn ON ignition switch, measure voltage between engine ground and “GRY/RED” wire terminal of MAP
sensor connector.
Is voltage 4 – 6 V? Go to Step 5.
Go to Step 4.
I4RS0B110019-03

Downloaded from www.Manualslib.com manuals search engine 1A-68 Engine General Information and Diagnosis:
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 MAP sensor and its circuit check
1) Connect scan tool to DLC with ignition switch OFF.
2) Turn ignition switch ON.
3) Check intake manifold pressure displayed on scan tool.
Is it 127 kPa (37.5 in.Hg)? Go to Step 3.
Intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection
Inspection in Section
00”.
3 MAP sensor power supply voltage check
1) Disconnect connector from MAP sensor with ignition
switch turned OFF.
2) Check for proper connection of MAP sensor at “GRY/ RED”, “RED/BLK” and “ORN” wire terminals.
3) Turn ON ignition switch, measure voltage between engine ground and “GRY/RED” wire terminal of MAP
sensor connector.
Is voltage 4 – 6 V? Go to Step 5.
Go to Step 4.
4 MAP sensor power supply circuit check
1) Disconnect connectors from A/C refrigerant pressure
sensor (if equipped with A/C) with ignition switch turned
OFF.
2) Turn ON ignition switch, measure voltage between engine ground and “GRY/RED” wire terminal of MAP
sensor connector.
Is voltage 4 – 6 V? Faulty A/C refrigerant
pressure sensor (if
equipped with A/C).
“GRY/RED” wire is open
or shorted to power
circuit.
5 MAP sensor ground circuit check
1) Measure resistance between “ORN” wire terminal of
MAP sensor connector and engine ground with ignition
switch turned OFF.
Is resistance below 5
Ω? Go to Step 7.
Go to Step 6.
I4RS0B110019-03

Downloaded from www.Manualslib.com manuals search engine 1A-70 Engine General Information and Diagnosis:
DTC Detecting Condition and Trouble Area
DTC Confirmation Procedure
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 at engine start: less than 30 °C (86 °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, clear DTC using scan tool.
3) Start engine and warm up to normal operating temperature. (ECT approx. 90 – 95 °C, 194 – 203 °F)
4) Run engine at idle speed for 10 min. or more.
5) 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.

DTC detecting condition Trouble area
Difference of maximum IAT minus minimum IAT is less than 0.3 °C
(32.5 °F) while ECT is over 70 °C (158 °F) after 10 min from cold
engine start (ECT is lower than 30 °C (86 °F) at engine start).
(2 driving cycle detection logic) • High resistance circuit
• MAF and IAT sensor
•ECM
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 IAT sensor and its circuit check
1) Connect scan tool to DLC with ignition switch turned
OFF.
2) Turn ignition switch to ON position.
3) Check intake air temp. displayed on scan tool.
Is –40
°C (–40 °F) or 119 °C (246 °F) indicated? Go to Step 3. Intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection
Inspection in Section
00”.

Downloaded from www.Manualslib.com manuals search engine 1A-72 Engine General Information and Diagnosis:
DTC P0112: Intake Air Temperature Sensor 1 Circuit LowS7RS0B1104024
Wiring Diagram
Refer to “DTC P0111: Intake Air Temperature Sensor 1 Circuit Range / Performance”.
DTC Detecting Condition and Trouble Area
DTC Confirmation Procedure1) With ignition switch turned OFF, connect scan tool.
2) Turn ON ignition switch and clear DTC using scan tool.
3) Start engine and run it for 10 sec.
4) Check 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.

8 Ground circuit check
1) Connect connectors to ECM.
2) Check for proper connection of MAF and IAT sensor
connector at “GRY/BLU” wire terminal.
3) Measure resistance between “GRY/BLU” wire terminal of MAF and IAT sensor connector and vehicle body
ground with ignition switch turned OFF.
Is resistance below 5
Ω? Go to Step 10. Go to Step 9.
9 Ground circuit check
1) Remove ECM from its br acket with ECM connectors
connected.
2) Measure resistance between “C37-55” terminal of ECM connector and vehicle body ground.
Is resistance below 3
Ω? “GRY/BLU” wire and/or
“ORN” wire is open or
high resistance circuit.
Poor “C37-55”
connection.
Faulty ECM ground
circuit.
If circuit is OK,
substitute a known-
good ECM and recheck.
10 IAT sensor check
1) Check IAT sensor according to “MAF and IAT Sensor
Inspection in Section 1C”.
Is it in good condition? Substitute a known-
good ECM and recheck.
Replace MAF and IAT
sensor.
Step Action Yes No
DTC detecting condition
Trouble area
IAT sensor output voltage is less than 0.15 V for 0.5 seconds
continuously.
(High intake air temperature (low voltage/low resistance))
(1 driving cycle detection logic) • IAT sensor circuit
• IAT sensor
•ECM

Downloaded from www.Manualslib.com manuals search engine 1A-74 Engine General Information and Diagnosis:
DTC P0113: Intake Air Temperature 1 Sensor Circuit HighS7RS0B1104025
Wiring Diagram
Refer to “DTC P0111: Intake Air Temperature Sensor 1 Circuit Range / Performance”.
DTC Detecting Condition and Trouble Area
NOTE
When DTC P0108 and P0118 are indicated together, it is possible that “ORN” wire circuit is open.

DTC Confirmation Procedure
1) With ignition switch turned OFF, connect scan tool.
2) Turn ON ignition switch and clear DTC using scan tool.
3) Start engine and run it for 10 sec.
4) Check 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.

DTC detecting condition Trouble area
IAT sensor output voltage is hi gher than 4.85 V for 0.5 seconds
continuously.
(Low intake air temperature (high voltage/high resistance))
(1 driving cycle detection logic) • IAT sensor circuit
• IAT sensor
•ECM
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 IAT sensor and its circuit check
1) Connect scan tool to DLC with ignition switch turned
OFF.
2) Turn ON ignition switch.
3) Check intake air temp. displayed on scan tool.
Is –40
°C (–40 °F) indicated? Go to Step 3. Intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection
Inspection in Section
00”.