radiator cooling SUZUKI SWIFT 2008 2.G Service Owner's Manual
Page 233 of 1496
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E23-45BLU/
ORNThrottle actuator 
control relay output
0 – 1 V Ignition switch turned ON. —
E23-46 LT GRN Radiator cooling 
fan relay No.1 
output 10 – 14 V
Ignition switch turned ON, 
engine coolant temp.: 
below 95 
°C (203 ° F), or 
A/C refrigerant pressure (if 
equipped with A/C): below 
600 kPa (87 psi) with A/C 
switch turned ON while 
engine is running. —
0 – 2 V Ignition switch turned ON, 
engine coolant temp.: 97.5 
°
C (207.5 ° F) or higher, or 
A/C refrigerant pressure (if 
equipped with A/C): 1100 
kPa (159.5 psi) or higher 
with A/C switch turned ON 
while engine is running.
E23-47 GRY A/C compressor 
relay output  10 – 14 V
Engine running, A/C 
switch OFF and blower 
selector at OFF position.
—
0 – 1 V Engine running, A/C 
switch ON and blower 
selector at 1st position or 
more.
E23-48 GRN Radiator cooling 
fan relay No.2 and 
No.3 output 10 – 14 V
Ignition switch turned ON, 
engine coolant temp.: 
below 100 
°C (212  °F), or 
A/C refrigerant pressure (if 
equipped with A/C): below 
1200 kPa (174 psi) with A/
C switch turned ON while 
engine is running. —
0 – 2 V Ignition switch turned ON, 
engine coolant temp.: 
102.5 
°C (216.5  °F) or 
higher, or A/C refrigerant 
pressure (if equipped with 
A/C): 1500 kPa (217.5 psi) 
or higher with A/C switch 
turned ON while engine is 
running.
E23-49 — — — — —
E23-50 — Ground for shield 
wire of APP sensor Below 0.3 V Ignition switch turned ON. —
E23-51 WHT Ground for APP 
sensor (sub) Below 0.3 V Ignition switch turned ON. —
E23-52 BLU Ground for APP 
sensor (main) Below 0.3 V Ignition switch turned ON. —
E23-53 — — — — —
E23-54 ORN Ground for sensors Below 0.3 V Ignition switch turned ON. —
Terminal 
No. Wire 
color Circuit Normal voltage Condition Remarks  
Page 243 of 1496
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Reference waveform No.32
VSS signal at 30 km/h (19 mph)
Resistance Check1) Remove ECM from its bracket  referring to “ECM Removal and Installation in Section 1C”.
CAUTION! 
Never touch terminals of ECM itself or connect voltmeter or ohmmeter (2).
 
2) Connect special tool to ECM connectors securely.
NOTE
Do not connect the other connector of special tool to ECM.
 
3) Check resistance between each pair of terminals of disconnected connectors (1) as listed in the following table.
CAUTION! 
• Be sure to connect ohmmeter probe from wire harness side of coupler.
• Be sure to turn OFF ignition switch for this check.
• Resistance in the following table represents that measured when parts temperature is 20  °C (68  °F).
 
Measurement 
terminal CH1: “E23-25” to “C37-58”
Oscilloscope 
setting CH1: 5 V/DIV, CH2: 5 V/DIV
TIME: 40 ms/DIV
Measurement 
condition • After warmed up to normal 
operating temperature
• Vehicle driving at 30 km/h (19  mph)
1. VSS signal for EPS control module
2. ON
3. OFF
I6RS0C110047-01
1
2
I4RS0A110086-02
Terminals CircuitStandard resistance Condition
C37-47 to E23-29 Heater of HO2S-2 4 – 15 Ω—
E23-46 to E23-1/16 Radiator cooling fan relay No.1 160 – 240 Ω —
E23-60 to E23-29 Main relay 160 – 240 ΩBattery disconnected 
and ignition switch 
turned ON
E23-15 to E23-29 Fuel pump relay 160 – 240 Ω —
C37-16 to E23-1/16 No.3 fuel injector 10.8 – 18.2 Ω —
C37-17 to E23-1/16 No.4 fuel injector
C37-4 to E23-1/16 EGR valve (st epping motor No.1 coil) 20 – 31 Ω —
C37-29 to E23-1/16 EVAP canister purge valve 28 – 35 Ω —
C37-2 to E23-1/16 No.2 fuel injector 10.8 – 18.2 Ω—  
Page 255 of 1496
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A/C System Circuits CheckS7RS0B1104084
Wiring Diagram
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/REDBLK/RED
BLK/YELBLK/YEL
BLK/YEL
BRN/WHT
12V
5V
12 
E23-1  
E23-60  
BLK/RED
LT GRN
BLK/REDE23-16  
E23-46  
L+
L–
H–
H
+
BLU/RED
BLK
BLUWHTBLK
BLU/BLK
BLU/RED
GRN
GRY
E23-48  
8
11
2
3BLU/WHT
REDWHTREDWHTE23-3E23-18
E23-19
6
BLK
WHT
BLK 12V
E23-47  GRY
WHT
YELBLU
WHT
BLK/YEL
RED/BLK
GRN/WHT
WHT/BLU1
713
14
5V
5V
4
E23-55C37-14GRY/REDRED
E23-54ORN 5V
E23-57WHT/BLK16
9
10
25
17
5
24
15
22
BLU/YEL
23212019
GRN
BLK
18
26
28
27
I6RS0C110042-01
1. Blower fan motor 11. Radiator cooling fan motor 21. “A/C COMP” fuse
2. Blower fan switch 12. Main relay 22. “IG ACC” fuse
3. A/C switch 13. ECM 23. “RDTR FAN” fuse
4. A/C refrigerant pressure sensor 14. Ignition switch 24. Junction block assembly
5. Blower motor relay 15. BCM 25. “IG2 SIG” fuse
6. Compressor relay 16. Evaporator outlet air temp. sensor 26. HVAC control module
7. A/C compressor 17. “BACK” fuse 27. For manual A/C
8. Radiator cooling fan relay No.1 18. Individual circuit fuse box No.1 28. For automatic A/C
9. Radiator cooling fan relay No.2 19. “HTR FAN” fuse
10. Radiator cooling fan relay No.3 20. “FI” fuse  
Page 256 of 1496
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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”.
• When A/C evaporator outlet air temp. is below 2.5  °C (36.5  °F), A/C remains OFF (“E23-47” terminal 
voltage becomes 10 – 14 V). This condition is not abnormal.
 
Step Action YesNo
1 Reception data check from BCM
1) Connect scan tool to DLC with ignition switch turned 
OFF.
2) Turn ON ignition switch.
3) Check DTC for reception data from BCM.
Is there DTC P1678? Go to applicable DTC 
diag. flow.
Go to Step 2.
2 A/C switch signal circuit check
1) Start engine and select “DATA LIST” mode on scan tool.
2) Check A/C switch signal under following conditions 
respectively.
A/C switch signal 
Engine running, A/C switch OFF: OFF
Engine running, A/C switch ON and blower speed 
selector turned 1st position or more: ON
Is check result satisfactory? Go to Step 3. Check A/C switch 
circuit.
3 DTC check of ECT sensor circuit
1) Check ECM for DTC of ECT sensor circuit.
Is there DTC P0116, DTC P0117 or DTC P0118? Go to applicable DTC 
diag. flow.
Go to Step 4.
4 Radiator cooling fan control system check
Is radiator cooling fan started when A/C and blower speed 
selector switch are turned ON with engine running? Go to Step 10. Go to Step 5.
5 Radiator cooling fan control circuit check
1) Check DTC with scan tool.
Is DTC P0480 displayed? Go to “DTC P0480: Fan 
1 (Radiator Cooling 
Fan) Control Circuit”.
Go to Step 6.  
Page 257 of 1496
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6A/C evaporator outlet air temp. sensor check
1) Disconnect connectors from ECM with ignition switch 
turned OFF.
2) Check for proper connection to “E23-57” and “E23-54”  wire terminals of ECM connector.
3) If OK, measure resistance between “E23-57” and “E23- 54” wire terminals of ECM connector.
Evaporator temp. sensor resistance
At 0  °C: 6.3 – 6.9 k Ω
At 25  °C: 1.8 – 2.2 k Ω
Is resistance within specification? Go to Step 7. Faulty A/C evaporator 
outlet air temp. sensor 
or its circuit.
7 DTC check of A/C refrigerant pressure sensor circuit
1) Connect scan tool to DLC with ignition switch turned 
OFF.
2) Turn ON ignition switch.
3) Check ECM for DTC of A/C refrigerant pressure sensor  circuit.
Is there DTC P0532 or DTC P0533? Go to applicable DTC 
diag. flow.
Go to Step 8.
8 A/C refrigerant pressure sensor voltage check
1) Check A/C refrigerant pressure sensor voltage referring 
to “Inspection of ECM and Its Circuits”.
Is voltage within specified value? Go to Step 9. Check amount of 
refrigerant. If OK, 
replace A/C refrigerant 
pressure sensor.
9 Radiator cooling fan check
1) Check radiator cooling fan referring to “Radiator Cooling 
Fan Motor On-Vehicle Inspection in Section 1F”.
Is check result satisfactory? Radiator cooling fan 
drive circuit malfunction. 
If circuit is OK, go to 
St ep  6 .
Replace radiator cooling 
fan motor.
10 A/C compressor control system check
Is A/C compressor started when A/C and blower speed 
selector switch are turned ON with engine running? A/C system is in good 
condition.
Go to Step 11.
Step Action Yes No
7
6
5
4
3
2
1
10
20 30
40 50
0
10
2030
60 70 80
ResistanceTemperatureI3RB0A110053-01  
Page 261 of 1496
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Radiator Cooling Fan Low Speed Control System CheckS7RS0B1104086
Wiring Diagram
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/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
BLKBLKE23-31  BLK
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
I6RS0C110043-01
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  
Page 262 of 1496
Downloaded from www.Manualslib.com manuals search engine 1A-212 Engine General Information and Diagnosis: 
Troubleshooting
WARNING! 
Keep hands, tools, and clothing away from engine cooling fan to help prevent personal injury. This fan 
is electric and can come on whether or not the engi ne is running. The fan can start automatically in 
response to the ECT sensor with the ig nition switch at the “ON” position.
 
NOTE
When measuring circuit voltage, resistance and/or  pulse signal at ECM connector, connect the special 
tool to ECM and/or the ECM connectors referri ng to “Inspection of ECM and Its Circuits”.
 
StepAction YesNo
1 Is there DTC(s) of ECT sensor circuit (DTC P0116 / P0117 / 
P0118) and/or radiator cooling fan circuit (DTC P0480)? Go to corresponding 
DTC flow.Go to Step 2.
2 Low speed radiator cooling fan control circuit check
1) Connect scan tool to DLC with ignition switch turned 
OFF.
2) Start engine and select “DATA LIST” mode on scan tool.
3) Warm up engine until coolant temp. is 97.5  °C, 207.5  °F 
or higher and A/C switch turns OFF (if equipped with A/
C). (If engine coolant temp. dose not rise, check engine 
cooling system or ECT sensor.)
Is radiator cooling fan started at low speed when engine 
coolant temp. reached above temp.? Radiator cooling fan low 
speed control system is 
in good condition.
Perform from Step 2 to 
Step 8 in DTC P0480 
diag. flow. If OK, Go to 
Ste p 3.
3 Radiator cooling fan control check
1) Disconnect radiator cooling fan control relays No. 2, and 
No. 3 from individual circuit  fuse box No.1 with ignition 
switch turned OFF.
2) Run engine when ECT is over 97.5  °C, 207.5  °F.
3) Measure voltage between vehicle body ground and  “BLU/RED” wire terminal of disconnected radiator 
cooling fan motor connector.
Is voltage 10 – 14 V? Go to Step 4.
“BLU/RED” wire is open 
or high resistance 
circuit.
4 Check radiator cooling fan wire circuit check
1) Turn ignition switch to OFF position.
2) Measure resistance between “BLK” wire terminal of 
disconnected radiator coolin g fan motor connector and 
vehicle body ground.
Is resistance below 1 
Ω? Go to Step 5. “BLK” wire is open or 
high resistance circuit.
5 Radiator cooling fan check
1) Check radiator cooling fan referring to “Radiator Cooling 
Fan Motor On-Vehicle Inspection in Section 1F”.
Is it in good condition? Substitute a known-
good ECM and recheck.
Faulty radiator cooling 
fan.  
Page 263 of 1496
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Radiator Cooling Fan High Speed Control System CheckS7RS0B1104087
Wiring Diagram
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/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
BLKBLKE23-31  BLK
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
I6RS0C110044-01
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  
Page 264 of 1496
Downloaded from www.Manualslib.com manuals search engine 1A-214 Engine General Information and Diagnosis: 
Troubleshooting
WARNING! 
Keep hands, tools, and clothing away from engine cooling fan to help prevent personal injury. This fan 
is electric and can come on whether or not the engi ne is running. The fan can start automatically in 
response to the ECT sensor with the ig nition switch at the “ON” position.
 
NOTE
When measuring circuit voltage, resistance and/or  pulse signal at ECM connector, connect the special 
tool to ECM and/or the ECM connectors referri ng to “Inspection of ECM and Its Circuits”.
 
StepAction YesNo
1 Is there DTC(s) of ECT sensor circuit (DTC P0116 / P0117 / 
P0118) and/or radiator cooling fan circuit (DTC P0480)? Go to corresponding 
DTC flow.Go to Step 2.
2 Low speed radiator cooling fan control circuit check
1) Connect scan tool to DLC with ignition switch turned 
OFF.
2) Start engine and select “DATA LIST” mode on scan tool.
3) Warm up engine until coolant temp. is 97.5  °C, 207.5  °F 
or higher and A/C switch turns OFF (if equipped with A/
C). (If engine coolant temp. dose not rise, check engine 
cooling system or ECT sensor.)
Is radiator cooling fan started at low speed when engine 
coolant temp. reached above temp.? Go to Step 3.
Perform from Step 2 to 
Step 5 in “Radiator 
Cooling Fan Low Speed 
Control System Check”.
3 High speed radiator cooling fan control circuit check
1) Start engine and select “DATA LIST” mode on scan tool.
2) Warm up engine until coolant temp. is 102.5  °C, 216.5  °F 
or higher and A/C switch turns OFF (if equipped with A/
C). (If engine coolant temp. dose not rise, check engine 
cooling system or ECT sensor.)
Is radiator cooling fan started at high speed when engine 
coolant temp. reached above temp? Radiator cooling fan 
control system is in 
good condition.
Perform from Step 9 to 
Step 14 in DTC P0480 
diag. flow.
If OK, Go to Step 4.
4 Radiator cooling fan control No. 2 and No. 3 check
1) Run engine when ECT is over 102.5  °C, 216.5  °F.
2) Measure voltage between vehicle body ground and  “E23-48” terminal of ECM connector.
Is voltage lower than 1.5 V? Go to Step 5.
Faulty ECM.
5 Radiator cooling fan No. 2 wire circuit check
1) Remove radiator cooling fan control relay No.2 with 
ignition switch turned OFF.
2) Measure voltage between “GRY” wire terminal of  disconnected radiator cooling fan control relay No. 2 
connector and vehicle body ground.
Is voltage 10 – 14 V? Go to Step 6.
“GRY” wire is open or 
high resistance circuit.
6 Radiator cooling fan No. 2 wire circuit check
1) Disconnect connector from radiator cooling fan motor 
with ignition swit ch turned OFF.
2) Measure resistance between “BLU/BLK” wire terminal of  disconnected radiator cooling fan control relay No. 2 
connector and vehicle body ground.
Is resistance infinity? Go to Step 7.
“BLU/BLK” wire is 
shorted to ground 
circuit.  
Page 265 of 1496
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7Radiator cooling fan No. 2 wire circuit check
1) Turn ON ignition switch.
2) Measure voltage between “BLU/BLK” wire terminal of 
disconnected radiator cooling fan control relay No. 2 
connector and vehicle body ground.
Is voltage 0 V? Go to Step 8. “BLU/BLK” wire is 
shorted to power supply 
circuit.
8 Radiator cooling fan control No. 2 check
1) Connect radiator cooling fan control relay No. 2 to 
individual circuit fuse box  No.1 with ignition switch 
turned OFF.
2) Run engine when ECT is over 102.5  °C, 216.5  °F.
3) Measure voltage between vehicle body ground and  “BLU/BLK” wire terminal of  disconnected radiator 
cooling fan motor connector.
Is voltage 10 – 14 V? Go to Step 10. Go to Step 9.
9 Radiator cooling fan control relay No.2 check
1) Remove radiator cooling fan control relay No.2 with 
ignition switch turned OFF.
2) Check radiator cooling fan control relay No.2 referring to  “Radiator Cooling Fan Relay  Inspection in Section 1F”.
Is it in good condition? “BLU/BLK” wire is open 
or high resistance 
circuit.
Faulty radiator cooling 
fan control relay No.2.
10 Radiator cooling fan No. 3 wire circuit check
1) Remove radiator cooling fan control relay No.3 with 
ignition switch turned OFF.
2) Measure resistance between vehicle body ground and  “BLK” wire terminal of disconnected radiator cooling fan 
control relay No. 3 connector in individual circuit fuse 
box No.1.
Is resistance below 1 
Ω? Go to Step 11. “BLK” wire is open or 
high resistance circuit.
11 Radiator cooling fan control No. 3 check
1) Connect radiator cooling fan control relay No. 3 to 
individual circuit fuse box  No.1 with ignition switch 
turned OFF.
2) Run engine when ECT is over 102.5  °C, 216.5  °F.
3) Measure resistance between vehicle body ground and  “BLU/WHT” wire terminal of disconnected radiator 
cooling fan motor connector.
Is resistance below 2 
Ω? Go to Step 13. Go to Step 12.
12 Radiator cooling fan control relay No. 3 check
1) Remove radiator cooling fan control relay No.3 with 
ignition switch turned OFF.
2) Check radiator cooling fan control relay No.3 referring to  “Radiator Cooling Fan Relay  Inspection in Section 1F”.
Is it in good condition? “BLU/WHT” wire is open 
or high resistance 
circuit.
Faulty radiator cooling 
fan control relay No.3.
13 Radiator cooling fan check
1) Check radiator cooling fan referring to “Radiator Cooling 
Fan Motor On-Vehicle Inspection in Section 1F”.
Is it in good condition? Substitute a known-
good ECM and recheck.
Faulty radiator cooling 
fan.
Step
Action YesNo