Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-103
DTC P0171 / P0172: Fuel System Too Lean / RichS6RW0D1104036
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 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 detecting condition Trouble area
DTC P0171:
Total fuel trim is higher than specified value or short term fuel trim is higher
than specified value for more than 1 min.
(2 driving cycle detection logic)
DTC P0172:
Total fuel trim is lower than specified value or short term fuel trim is lower
than specified value for more than 1 min.
(2 driving cycle detection logic)• Vacuum leakage
• Exhaust gas leakage
• Fuel pressure out of specification
• Fuel injector malfunction
• Heated oxygen sensor-1 malfunction
• MAF sensor malfunction
• ECT sensor malfunction
Downloaded from www.Manualslib.com manuals search engine 1A-104 Engine General Information and Diagnosis:
DTC Troubleshooting
NOTE
Before this troubleshooting is performed, read the precautions for DTC troubleshooting referring to
“Precautions for DTC Troubleshooting”.
Step Action Yes No
1Was “Engine and Emission Control System Check”
performed?Go to Step 2. Go to “Engine and
Emission Control
System Check”.
2Is there DTC(s) other than fuel system (DTC P0171 /
P0172)?Go to applicable DTC
diag. flow.Go to Step 3.
3Intake 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.
4Fuel pressure check
1) Check fuel pressure referring to “Fuel Pressure Check”.
Is check result satisfactory?Go to Step 5. Repair or replace
defective part.
5Fuel 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.
6Visual inspection
1) Check MAF sensor and air intake system.
• Objects which block measuring 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.
7MAF sensor for performance check
1) With ignition switch turned 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 Air Flow Circuit
Range / Performance”.
8ECT 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.
9HO2S-1 for performance check
1) Check HO2S-1 referring to Step 3 of “DTC P0131 /
P0132: O2 Sensor (HO2S) Circuit Low Voltage / High
Voltage (Sensor-1)”.
Is check result satisfactory?Substitute a known-
good ECM and recheck.Faulty HO2S-1 or its
circuit.
Downloaded from www.Manualslib.com manuals search engine 1A-120 Engine General Information and Diagnosis:
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) Run engine at idle for 10 min.
5) Drive vehicle and increase engine speed 3000 rpm in 3rd gear or “3” range.
6) Release accelerator pedal and with engine brake applied, keep vehicle coasting for 5 sec. or more. (Keep fuel cut
condition for 5 sec. or more) If fuel cut condition is not kept for 5 sec. or more, coast down a slope in engine speed
1000 – 3000 rpm for 5 sec. or more.
7) Stop vehicle and run engine at idle.
8) For european market model, check whether EGR system readiness/monitoring test has completed or not by using
scan tool.
If evaporative system readiness/monitoring test has not completed, check vehicle conditions (environmental) and
repeat Steps 3) through 7).
9) Check DTC and pending DTC.DTC detecting condition Trouble area
DTC P0401:
Difference in intake manifold absolute pressure between opened EGR valve and closed
EGR valve is smaller than specified value.
(2 driving cycle detection logic, monitoring once / 1 driving)
DTC P0402:
Difference in intake manifold absolute pressure between opened EGR valve and closed
EGR valve is larger than specified value.
(2 driving cycle detection logic, monitoring once / 1 driving)• EGR valve
• EGR passage
• MAP sensor
•ECM
Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-125
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 (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 or more
• Altitude (barometric pressure): 2500 m, 8200 ft or less (560 mmHg, 74.4 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 40 – 50 mph, 60 – 80 km/h.
4) Keep above vehicle speed for 10 min. or more (Throttle valve opening is kept constant in this step).
5) Stop vehicle.
6) For european market model, check whether catalyst monitoring readiness/monitoring test has completed or not by
using scan tool.
If evaporative system readiness/monitoring test has not completed, check vehicle conditions (environmental) and
repeat Steps 3) through 5).
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”.
Step Action Yes No
1Was “Engine and Emission Control System Check”
performed?Go to Step 2. Go to “Engine and
Emission Control
System Check”.
2Exhaust 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.
3HO2S-2 output voltage check
1) Check output voltage of HO2S-2 referring to “DTC
P0137 / P0138: O2 Sensor (HO2S) Circuit Low Voltage /
High Voltage (Sensor-2)”.
Is check result satisfactory?Replace exhaust
manifold (built in warm
up three way catalytic
converter) and exhaust
center pipe (built in
three way catalytic
converter).Check “BRN” and / or
“ORN” wires for open
and short, and
connections for poor
connection.
If wires and connections
are OK, replace HO2S-
2.
Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-181
Reference waveform No.1
Fuel injector signal (1) with engine idlingReference waveform No.2
No.1 fuel injector signal (2) with engine idling E01-58RED/
BLKA/C condenser fan
relay
(if equipped with A/
C)0 – 1 VBlower speed selector ON
A/C or defroster switch ON
Engine running or Engine
coolant temperature at
more than 110 °C (230 °F)
with engine running.—
10 – 14 VExcept the above
mentioned condition with
engine running
E01-59 — — — — —
E01-60BRN/
WHTMain power supply
relay output10 – 14 V Ignition switch turned OFF.
—
0 – 2 V Ignition switch turned ON. Terminal
No.Wire
colorCircuit Normal voltage Condition Remarks
Measurement
terminalCH1: “C01-2” to “C01-58”
Oscilloscope
settingCH1: 20 V/DIV
TIME: 1 ms/DIV
Measurement
condition• After warmed up to normal
operating temperature
• Engine at specified idle speed
2. Fuel injection pulse width: 2-4 msec. 3. 10 – 14 V
I4RS0B110050-01
Measurement
terminalCH1: “C01-20” to “C01-58”
CH2: “C01-1” to “C01-58”
Oscilloscope
settingCH1: 5 V/DIV, CH2: 20 V/DIV
TIME: 40 ms/DIV
Measurement
condition• After warmed up to normal
operating temperature
• Engine at specified idle speed
[A]: For VVT model
[B]: For non-VVT model
1. Cylinder reference signal (CMP reference signal)
3. 720° crank angle
I4RS0B110051-01
Downloaded from www.Manualslib.com manuals search engine 1A-210 Engine General Information and Diagnosis:
Troubleshooting
NOTE
• Before performed trouble shooting, be sure to read the “Precautions of ECM Circuit Inspection”.
• When measuring circuit voltage, resistance and/or pulse signal at ECM connector, connect the
special tool to ECM and/or the ECM connectors referring to “Inspection of ECM and Its Circuits”.
Step Action Yes No
1DTC check
1) Connect scan tool to DLC with ignition switch turned
OFF.
2) Turn ON ignition switch and check DTC.
Is there DTC U0073 and/or U0140?Go to applicable DTC
diag. flow.Go to Step 2.
2Electric load signal circuit check
1) Start engine and select “Data List” mode on scan tool.
2) Check electric load signal under following conditions
respectively.
Blower fan signal (Manual A/C model)
Blower speed selector turned OFF, 1st or 2nd
position: OFF
Blower speed selector turned to 3rd position or
more: ON
Blower fan signal (Automatic A/C model)
Blower speed selector OFF or 1st position: OFF
Blower speed selector turned to 3rd position or
more: ON
Radiator fan signal
Engine coolant temperature is lower than 100 °C
(212 °F): OFF
Engine coolant temperature is higher than 100 °C
(212 °F): ON
Electric load signal
Engine running, rear defogger switch, small light or
headlight switch OFF: OFF
Engine running, rear defogger switch, small light or
headlight switch ON: ON
Is check result satisfactory?Electric load signal
circuit is in good
condition.Check defective signal
circuit.
Downloaded from www.Manualslib.com manuals search engine 1B-1 Aux. Emission Control Devices:
Engine
Aux. Emission Control Devices
Diagnostic Information and Procedures
EGR System Inspection (If Equipped)S6RW0D1204001
1) Connect SUZUKI scan tool to data link connector
(DLC) (1) with ignition switch turned OFF.
2) Turn ON ignition switch and erase DTC using
“Delete” in “DTC” menu of scan tool.
3) Start engine and warm it up to normal operating
temperature, then select “Data List” mode on scan
tool.
4) Make sure that vehicle condition is as follows.
• Vehicle speed = 0 km/h (0 KPH)
• Engine speed ≤ 900 rpm
• Engine coolant temp. ≥ 90 °C, 164 °F5) With engine idling (without depressing accelerator
pedal), open EGR valve by using “Step EGR
Control” mode in “Engine / Active Test” menu. In this
state, as EGR valve opening increases engine idle
speed drops. If not, possible cause is clogged EGR
gas passage, stuck or faulty EGR valve.
Special tool
(A): SUZUKI scan tool (SUZUKI-SDT)
Repair Instructions
EVAP Canister Purge InspectionS6RW0D1206001
NOTE
Before inspection, check to make sure that
gear shift lever is in neutral position and that
parking brake lever is pulled all the way up.
1) Disconnect purge hose (1) from purge pipe.
2) Place finger against the end of disconnected hose
and check that vacuum is not felt there when engine
is cool and running at idle speed. If check result is
not satisfactory, check EVAP canister purge valve,
wire harness and ECM.
EVAP Canister Purge Valve and Its Circuit
Inspection
S6RW0D1206002
WARNING!
Do not apply vacuum by mouth; otherwise
harmful fuel vapor can be breathed in.
CAUTION!
Do not apply vacuum more than –86 kPa (–
12.47 psi); otherwise EVAP canister purge
valve could be damaged.
(A) 1I5RW0C110011-01
1
I5RW0A120006-01
Downloaded from www.Manualslib.com manuals search engine Engine Electrical Devices: 1C-7
Engine Coolant Temperature (ECT) Sensor
Removal and Installation
S6RW0D1306008
Removal
1) Disconnect negative cable at battery.
2) Drain coolant referring to “Cooling System Draining
in Section 1F”.
WARNING!
To avoid danger of being burned, do not
remove radiator cap while engine and
radiator are still hot.
Scalding fluid and steam can be blown out
under pressure if cap is taken off too soon.
3) Remove air intake pipe.
4) Disconnect connector from ECT sensor (1).
5) Remove ECT sensor from water outlet.
Installation
Reverse removal procedure noting the following.
• Clean mating surfaces of ECT sensor and water
outlet.
• Check O-ring for damage and replace, if necessary.
• Tighten ECT sensor (1) to specified torque.
Tightening torque
ECT sensor (a): 15 N·m (1.5 kgf-m, 11.0 lb-ft)
• Connect connector to ECT sensor securely.
• Refill coolant referring to “Cooling System Flush and
Refill in Section 1F”.
Engine Coolant Temperature (ECT) Sensor
Inspection
S6RW0D1306009
Immerse temperature sensing part of ECT sensor (1) in
water (or ice) and measure resistance between sensor
terminals while heating water gradually.
If measured resistance doesn’t show such characteristic
as shown, replace ECT sensor.
1
I2RH0B130008-01
1,(a)
I2RH0B130009-01
I5RW0A130007-01