2008 SUZUKI SWIFT Service Workshop Manual

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-119
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 Description”.
2 EGR valve power supply circuit check
1) Remove air intake pipe.
2) With ignition switch turned OFF, disconnect EGR valve
connector.
3) With ignition switch turned ON, measure voltage between “BLK/RED” wire terminal of EGR valve
connector and vehicle body ground.
Is check voltage 10 – 14 V? Go to Step 3.
“BLK/RED” wire is open
circuit.
3 Wire circuit check
1) Disconnect connectors from ECM with ignition switch
turned OFF.
2) Turn ON ignition switch.
3) Measure voltage between engine ground and each “GRN/RED”, “GRN/ORN”, “W HT/RED”, “BRN/YEL” wire
terminals of EGR valve connector.
Is each voltage 0 V? Go to Step 4.
Faulty wire(s) are
shorted to other circuit.
If wires are OK,
substitute a known-
good ECM and recheck.
4 Wire circuit check
1) With ignition switch turned OFF, measure resistance
between engine ground and each “GRN/RED”, “GRN/
ORN”, “WHT/RED”, “BRN/YEL” wire terminals of EGR
valve connector.
Is resistance infinity? Go to Step 5.
Faulty wire(s) are
shorted to ground
circuit.
If wires are OK,
substitute a known-
good ECM and recheck.
5 Short circuit check for EGR valve control circuit
1) With ignition turned OFF, measure resistance between
each EGR valve control circ uit wire (“GRN/RED”, “GRN/
ORN”, “WHT/RED” and “BRN/ YEL” wire) and each EGR
valve control circuit wire.
Is each resistance infinity? Go to Step 6.
Faulty wire(s) are short
circuit.
6 EGR valve stepper motor coil circuit check
1) With ignition switch turned OFF, connect EGR valve
connector.
2) Measure resistance between “E23-1/16” and each “C37- 4”, “C37-3”, “C37-19”, “C37-18” terminals of ECM
connector.
Is each resistance 20 – 31
Ω at 20 °C, 68 °F? Faulty ECM. Substitute
a known-good ECM and
recheck.
Go to Step 7.
7 EGR valve check
1) Check EGR valve resistance referring to “EGR Valve
Inspection in Section 1B”.
Is resistance within specified value? Faulty wire(s) are open
or high resistance
circuit. If wires are OK,
substitute a known-
good ECM and recheck.Faulty EGR valve.

Downloaded from www.Manualslib.com manuals search engine 1A-120 Engine General Information and Diagnosis:
DTC P0420: Catalyst System Efficiency below ThresholdS7RS0B1104046
System and Wiring Diagram
Circuit Description
ECM monitors oxygen concentration in the exhaust gas which has passed the warm up three way catalytic converter
by HO2S-2. When the catalyst is functioning properly, the variation cycle of HO2S-2 output voltage (oxygen
concentration) is slower than that of HO2S-1 output voltage because of the amount of oxygen in the exhaust gas
which has been stored in warm up three way catalytic converter.
Reference
Oscilloscope waveforms
C37-11
C37-10
C37-57
WHT
BRN
1
3 2
4
5 VYELYEL
BLUWHTBLUWHT 5
I4RS0A110037-01
1. HO2S-1
3. Warm up three way catalytic converter 5. ECM
2. HO2S-2 4. Three way catalytic converter
I2RH01110102-01

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-121
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.

Downloaded from www.Manualslib.com manuals search engine 1A-122 Engine General Information and Diagnosis:
DTC P0443: Evaporative Emission System Purge Control Valve CircuitS7RS0B1104047
Wiring Diagram
DTC Detecting Condition and Trouble Area3
HO2S-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)” and “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
“YEL” wires for open
and short, and
connections for poor
connection.
If wires and connections
are OK, replace HO2S-
2.
Step Action Yes No
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 33 1
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 48 32 31
34353637
40
42 39 38
44
45 43 41 331
1213
238
BLK/WHT
BLK/RED
BLK/RED
WHTBLK/YELBLK/YEL
BLK/YEL
GRN
BRN/WHT
12V 5V
5
4 2
3 6E23-29
E23-1
E23-60
C37-58
C37-15 C37-30
BLK/ORN
BLKBLKE23-31 BLK
7
8
BLK/REDBLK/REDE23-16
1
C37-29 BLU/BLK
I6RS0C110020-02
1. EVAP canister purge valve
4. Main fuse box7. “FI” fuse
2. Main relay 5. Ignition switch8. “IG ACC” fuse
3. “IG COIL” fuse 6. ECM
DTC detecting conditionTrouble area
Monitor signal of EVAP canister purge valve is different from
command signal. (Circuit open or short)
(2 driving cycle detection logic) • EVAP canister purge valve
• EVAP canister purge valve circuit
•ECM

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-123
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.

1) With ignition switch OFF, connect scan tool to DLC.
2) Turn ON ignition switch and clear DTC using scan tool.
3) Start engine and warm up normal operating temperature.
4) Drive vehicle at more than 40 km/h, 25 mph for 5 min. or more.
5) Check DTC and pending DTC.
DTC Troubleshooting
WARNING!
In order to reduce risk of fire and personal injury, this work must be performed in a well ventilated area
and away from any open flames such as gas water heater.

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 EVAP canister purge power supply circuit check
1) Turn OFF ignition switch and disconnect connector from
EVAP canister purge valve.
2) Measure voltage between engine ground and “BLK/ RED” wire terminal of EVAP canister purge valve
connector with ignition switch turned ON.
Is it voltage 10 – 14 V? Go to Step 3.
“BLK/RED” wire is open
circuit.
3 Wire circuit check
1) Disconnect connectors from ECM with ignition switch
turned OFF.
2) Measure resistance between “C37-29” terminal of ECM connector and vehicle body ground.
Is resistance infinity? Go to Step 4.
“BLU/BLK” wire is
shorted to ground
circuit.
4 Wire circuit check
1) Measure voltage between “C37-29” terminal of ECM
connector and vehicle body ground with ignition switch
turned ON.
Is voltage 0 V? Go to Step 5.
“BLU/BLK” wire is
shorted to other circuit.

Downloaded from www.Manualslib.com manuals search engine 1A-124 Engine General Information and Diagnosis:
DTC P0480: Fan 1 (Radiator Cooling Fan) Control CircuitS7RS0B1104050
Wiring Diagram5
Wire circuit check
1) Connect connector to purge control valve with ignition
switch turned OFF.
2) Turn ON ignition switch and measure voltage between “C37-29” terminal of ECM connector and vehicle body
ground.
Is it voltage 10 – 14 V? Go to Step 6. “BLU/BLK” wire is open
circuit.
6 EVAP canister purge control valve check
1) Check EVAP canister purge control valve referring to
“EVAP Canister Purge Valve Inspection in Section 1B”.
Is it in good condition? Go to Step 7. Faulty EVAP canister
purge control valve.
7 EVAP canister purge control circuit check
1) With ignition switch turn OFF, measure resistance
between “E23-1/16” terminal and “C37-29” terminal of
ECM connector.
Is resistance below 40
Ω at 20 °C, 68 °F? Faulty ECM. Substitute
a known-good ECM and
recheck.
“BLK/RED” and/or
“BLU/BLK” wire are high
resistance circuit.
Step Action Yes No
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/REDBLK/RED
BLK/YELBLK/YEL
BLK/YEL
BRN/WHT
12V
5V5V
2
8
E23-1
E23-60
C37-58
C37-15 C37-30
BLK/ORN
BLKBLKE23-31BLK
BLK/RED
LT GRN
BLK/REDE23-16
E23-46
L+
L–
H–
H
+
BLU/RED
BLK
BLUWHTBLK
BLU/BLK
BLU/RED
4
GRN
GRY
E23-48
LT GRN
ORN
C37-24
C37-55
35
6
7
10
9
1
I6RS0C110022-02
1. Individual circuit fuse box No.1
5. Radiator cooling fan relay No. 3 9. “FI” fuse
2. Main relay 6. Radiator cooling fan motor10. “RDTR FAN” fuse
3. Radiator cooling fan relay No. 1 7. ECT sensor
4. Radiator cooling fan relay No. 2 8. ECM

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-125
DTC Detecting Condition and Trouble Area
DTC Confirmation Procedure1) Turn OFF ignition switch.
2) Clear DTC with ignition switch turned ON.
3) Run engine at idle speed.
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
Monitor signal of radiator cooling fan relay is different from
command signal.
(1 driving cycle detection logic) • Radiator cooling fan relay circuit malfunction
• Radiator cooling fa
n relay malfunction
• ECM 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 Circuit fuse check
1) Check “RDTR FAN” fuse (1) in individual circuit fuse box
No.1 with ignition switch turned OFF.
Is “RDTR FAN” fuse in good condition? Go to Step 3.
Check for short in
circuits connected to
this fuse.
1
I4RS0A110022-01

Downloaded from www.Manualslib.com manuals search engine 1A-126 Engine General Information and Diagnosis:
3Wire circuit check
1) Disconnect radiator cooling fan relay No. 1 (1) from
individual circuit fuse box No .1 (2) with ignition switch
turned OFF.
2) Turn ON ignition switch, measure voltage between each engine ground to “BLK/RED” and “GRY” wire terminal.
Is voltage 10 – 14 V? Go to Step 4. Open wire in “BLK/RED”
and/or “GRY” wire are
open circuit.
4 Wire circuit check
1) Connect radiator cooling fan relay No. 1 to individual
circuit fuse box No.1 with ignition switch turned OFF.
2) Remove ECM from its br acket with ECM connectors
connected.
3) Turn ON ignition switch, ma ke sure that A/C switch is
OFF position.
4) Measure voltage between vehicle body ground and “E23-46” terminal of ECM connector when engine
coolant temp. is below 95 °C, 203 °F.
Is voltage 10 – 14 V? Go to Step 8.
Go to Step 5.
5 Wire circuit check
1) Disconnect connectors from ECM with ignition switch
turned OFF.
2) Disconnect radiator cooling fan relay No. 1 from individual circuit fuse box No.1.
3) Measure resistance between “E23-46” terminal of ECM connector and vehicle ground.
Is resistance infinity? Go to Step 6.
“LT GRN” wire is
shorted to ground
circuit.
6 Wire circuit check
1) Turn ON ignition switch.
2) Measure voltage between “E23-46” terminal of ECM
connector and vehicle body ground.
Is voltage 0 V? Go to Step 7.
“LT GRN” wire is
shorted to other circuit.
7 Radiator cooling fan relay No. 1 check
1) Check radiator cooling fan relay No. 1 referring to
“Radiator Cooling Fan Relay Inspection in Section 1F”.
Is check result satisfactory? “LT GRN” wire is open
circuit.
Replace relay.
Step
Action YesNo
1
2
I7RS0A110010-01