2008 SUZUKI SWIFT vehicle speed signal circuit

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-129
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.

1) With ignition switch turned OFF, connect scan tool.
2) Turn ON ignition switch and clear DTC using scan tool.
3) Warm up engine to normal operating temperature.
4) M/T model
a) Drive vehicle at 4000 rpm (e ngine speed) with 3rd gear.
b) Release accelerator pedal and with engine brake applied, keep vehicle coasting for 6 sec. or more (fuel cut condition for 5 sec. or more) and stop vehicle.
A/T model
a) Drive vehicle at more than 3000 rpm for 10 sec.
5) Check pending DTC and 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
• Vehicle speed signal is not input while fuel is cut at deceleration for 4 seconds continuously at 3600 rpm or
less.
• Vehicle speed signal is not input even if engine is running with more than 3000 rpm at D-Range for 4 sec. (A/T model).
(2 driving cycle detection logic) • Wheel speed sensor and/or its circuit
• ABS/ESP®
control module
•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 Vehicle speed signal check
Is vehicle speed displayed on scan tool in Step 4) and 5) of
“DTC Confirmation Procedure”? Intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection
Inspection in Section
00”.Go to Step 3.
3 DTC check in ABS/ESP ® control module
1) Check ABS/ESP ® control module for DTC.
Is there any DTC of wheel speed sensor or CAN
communication system? Go to applicable DTC
diag. flow.
Substitute a know-good
ECM and recheck.

Downloaded from www.Manualslib.com manuals search engine 1A-140 Engine General Information and Diagnosis:
DTC Confirmation Procedure1) With ignition switch turned OFF, connect scan tool to DLC.
2) Turn ON ignition switch and clear DTC.
3) Make sure that all accessory switch is tuned OFF.
4) Start engine and warm it up to normal operating temperature (ECT approx. 90 – 95 °C, 193 – 203 °F).
5) Turn ON following accessory switch. • Head lights switch.
• Blower motor switch (max position).
• Rear defogger switch.
6) Increase engine speed to 4000 rpm and keep it for 10 sec. or more.
7) Decrease engine speed to idle.
8) 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.

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 Generator control circuit check
1) Disconnect connector from generator and ECM with
ignition switch turned OFF.
2) Check for proper connection of wire terminal to generator connector and to ECM connector.
3) If connections are OK, check generator control (generator “C” terminal) circuit and field coil monitor
(generator “FR” terminal) circuit for the following.
• Resistance of each generato r control wire and field
coil monitor wire between generator connector and
ECM connector is less than 1 Ω (continuity check)
• Resistance between generator control wire and field coil monitor wire of generator connector is infinity
(insulation check)
• Resistance between each generator control wire and field coil monitor wire of generator connector and
vehicle body ground is infinity (ground circuit short
check)
• Voltage between each generator control wire and field
coil monitor wire of generator connector and vehicle
body ground is 0 V with ignition switch tuned ON
(power circuit short check)
Are they in good condition? Go to Step 3.
Repair or replace
defective wire.
3 Generator check
1) Check for generator output referring to “Generator Test
(Undercharged Battery Check) in Section 1J” and
“Generator Inspection in Section 1J”.
Is check result satisfactory? Substitute a known
good ECM and recheck.
Repair or replace
generator.

Downloaded from www.Manualslib.com manuals search engine 1A-176 Engine General Information and Diagnosis:
Terminal No. Wire
color Circuit Normal voltage Condition Remarks
C37-1 BLU/
YEL Fuel injector No.1
output 10 – 14 V Ignition switch turned ON. —
*0 – 0.6 V ↑↓
10 – 14 V
(“Reference
waveform No.1: ”,
“Reference waveform No.2: ” and
“Reference waveform No.22: ”) Engine running at idle
after warmed up engine.
Output signal is active low
pulse. Pulse frequency
varies depending on
engine speed.
C37-2 BLU/
WHT Fuel injector No.2
output 10 – 14 V Ignition switch turned ON. —
*0 – 0.6 V ↑↓
10 – 14 V
(“Reference
waveform No.1: ” and
“Reference waveform No.3: ”) Engine running at idle
after warmed up engine.
Output signal is active low
pulse. Pulse frequency
varies depending on
engine speed.
C37-3 GRN/
ORN EGR valve
(stepper motor coil
2) output 10 – 14 V Ignition switch turned ON. —
*0 – 1 V ↑↓
10 – 14 V
(“Reference
waveform No.4: ”) Ignition switch is turned to
ST (cranking) position. Output signal is active low
duty pulse. Number of
pulse generated times
varies depending on
vehicle condition.
C37-4 GRN/
RED EGR valve
(stepper motor coil
1) output 10 – 14 V Ignition switch turned ON. —
*0 – 1 V
↑↓
10 – 14 V
(“Reference
waveform No.4: ”) Ignition switch is turned to
ST (cranking) position. Output signal is active low
duty pulse. Number of
pulse generated times
varies depending on
vehicle condition.
C37-5 GRN/
WHT Ignition coil No.2
and No.3 output 0 – 0.6 V Ignition switch turned ON. —
*0 – 0.6 V ↑↓
3 – 5 V
(“Reference
waveform No.5: ” and
“Reference waveform No.6: ”) Engine running at idle
after warmed up engine.
Output signal is active
high pulse. Pulse
frequency varies
depending on engine
speed.
C37-6 GRN/
YEL Ignition coil No.1
and No.4 output 0 – 0.6 V Ignition switch turned ON. —
*0 – 0.6 V ↑↓
3 – 5 V
(“Reference
waveform No.6: ”,
“Reference waveform No.7: ” and
“Reference waveform No.22: ”
)Engine running at idle
after warmed up engine.
Output signal is active
high pulse. Pulse
frequency varies
depending on engine
speed.
C37-7 — —— — —
C37-8 BRN/
WHT Generator field coil
monitor signal 10 – 14 V Ignition switch turned ON.
Signal is duty pulse. Duty
ratio varies depending on
vehicle condition.
*0 – 1 V
↑↓
10 – 14 V
(“Reference
waveform No.8: ”) Engine running at idle
after warmed up engine.
C37-9 — —— — —

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-177
C37-10 WHTOxygen signal of
HO2S-1 0 – 1 V Ignition switch turned ON.
—
*Deflects between
over 0.5 V and under 0.45 V
(“Reference
waveform No.10: ” and “Reference
waveform No.11: ”) While engine running at
2,000 r/min. for 1 min. or
longer after warmed up.
C37-11 BRN Oxygen signal of
HO2S-2 4 – 5 V Ignition switch turned ON.
—
*Deflects between
over 0.5 V and under 0.45 V
(“Reference
waveform No.12: ”) While engine running at
2,000 r/min. or more after
vehicle running over 30
km/h, 19 mph for 5 min.
C37-12 WHT CAN (low)
(communication
line (active low
signal) to TCM (A/T
model) *0.5 – 2.5 V
(“Reference
waveform No.13: ”) Ignition switch turned ON
with engine stop. CAN communication line
signal is pulse. Pulse
signal displayed with a
regular frequency which
varies depending on
engine condition.
C37-13 RED CAN (high)
communication line
(active high signal)
to TCM (A/T
model) *2.5 – 4.5 V
(“Reference
waveform No.13: ”)
C37-14 GRY/
RED Output of 5 V
power source for
MAP sensor, A/C
refrigerant
pressure sensor
4.5 – 5.5 V Ignition switch turned ON. —
C37-15 BLK Ground for ECM Below 0.3 V Ignition switch turned ON. —
C37-16 BLU/
RED Fuel injector No.3
output 10 – 14 V Ignition switch turned ON. —
*0 – 0.6 V ↑↓
10 – 14 V
(“Reference
waveform No.1: ” and
“Reference waveform No.14: ”) Engine running at idle
after warmed up engine.
Output signal is active low
pulse. Pulse frequency
varies depending on
engine speed.
C37-17 BLU/
ORNFuel injector No.4
output 10 – 14 V Ignition switch turned ON. —
*0 – 0.6 V ↑↓
10 – 14 V
(“Reference
waveform No.1: ” and
“Reference waveform No.15: ”) Engine running at idle
after warmed up engine.
Output signal is active low
pulse. Pulse frequency
varies depending on
engine speed.
C37-18 BRN/
YEL EGR valve
(stepper motor coil
4) output 10 – 14 V Ignition switch turned ON. —
*0 – 1 V ↑↓
10 – 14 V
(“Reference
waveform No.4: ”) Ignition switch is turned to
ST (cranking) position. Output signal is active low
duty pulse. Number of
pulse generated times
varies depending on
vehicle condition.
C37-19 WHT/
RED EGR valve
(stepper motor coil
3) output 10 – 14 V Ignition switch turned ON. —
*0 – 1 V ↑↓
1

0 – 14 V
(“Reference
waveform No.4: ”) Ignition switch is turned to
ST (cranking) position. Output signal is active low
duty pulse. Number of
pulse generated times
varies depending on
vehicle condition.
Terminal
No. Wire
color Circuit Normal voltage
ConditionRemarks

Downloaded from www.Manualslib.com manuals search engine 1A-178 Engine General Information and Diagnosis:
C37-20RED/
YEL CMP sensor signal 0 – 1 V or 4 – 5 V Ignition switch turned ON. —
*0 – 0.6 V↑↓
4 – 5 V
(“Reference
waveform No.16: ” and “Reference
waveform No.17: ”) Engine running at idle
after warmed up engine.
Sensor signal is pulse.
Pulse frequency varies
depending on engine
speed.
(6 pulses are generated
per 1 camshaft revolution.)
C37-21 PNK CKP sensor signal 0 – 1 V or 4 – 5 V Ignition switch turned ON. —
*4 – 5 V↑↓
0 – 0.6 V
(“Reference
waveform No.16: ” and “Reference
waveform No.17: ”) Engine running at idle
after warmed up engine. Sensor signal is pulse.
Pulse frequency varies
depending on engine
speed.
(30 (36 – 6) pulses are
generated per 1
crankshaft revolution.)
C37-22 — — — — —
C37-23 PNK/
BLU Electric load
current sensor
signal 3.8 – 4.2 V Ignition switch turned ON.
—
3.0 – 3.4 V
Ignition switch turned ON
and headlight switch
turned ON (HI beam).
2.3 – 2.7 V Ignition switch turned ON,
headlight switch turned
ON (HI beam) and blower
selector at HI position.
C37-24 LT GRN ECT sensor signal 3.3 – 3.8 V
Ignition switch turned ON,
ECT at 0
°C, 32 °F.
—
1.38 – 1.72 V Ignition switch turned ON,
ECT at 50
°C, 122 °F.
0.40 – 0.53 V Ignition switch turned ON,
ECT at 100
°C, 212 °F.
C37-25 BLK/
YEL IAT sensor signal 3.18 – 3.67 V
Ignition switch turned ON,
IAT at 0
°C, 32 °F.
—
1.32 – 1.65 V Ignition switch turned ON,
IAT at 40
°C, 104 °F.
0.46 – 0.60 V Ignition switch turned ON,
IAT at 80
°C, 176 °F.
C37-26 GRN/
BLK MAF sensor signal 0.5 – 1.5 V
Ignition switch turned ON
with engine at stop.
—
1.5 – 2.0 V
(“Reference
waveform No.18: ”) Wh

en engine running at
specified idle speed after
warmed up.
C37-27 GRY Ground for MAF
sensor Below 0.3 V Ignition switch turned ON.
—
C37-28 BLU/
YEL Generator control
signal output *0 – 0.6 V
↑↓
5 – 8 V
(“Reference
waveform No.19: ”) Engine running at idle
speed, headlight switch
turned ON.
Output signal is active low
duty pulse. Duty ratio
varies depending on
vehicle condition.
C37-29 BLU/
BLK EVAP canister
purge valve output 10 – 14 V
Ignition switch turned ON
with engine at stop. —
*0 – 0.6 V ↑↓
10 – 14 V
(“Reference
waveform No.20: ”) Set EVAP canister purge
valve at 52% by using
“Misc Test” of scan tool.
Output signal is active low
duty pulse. Duty ratio
varies depending on
vehicle condition.
C37-30 BLK Ground for ECM Below 0.3 V Ignition switch turned ON. —
C37-31 — —— — —
Terminal
No. Wire
color Circuit Normal voltage
ConditionRemarks

Downloaded from www.Manualslib.com manuals search engine 1A-180 Engine General Information and Diagnosis:
C37-50 —Ground of ECM for
shield wire Below 0.3 V Ignition switch turned ON. —
C37-51 — Ground of ECM for
shield wire Below 0.3 V Ignition switch turned ON. —
C37-52 — Ground of ECM for
shield wire Below 0.3 V Ignition switch turned ON. —
C37-53 RED/
BLK MAP sensor signal Approx. 4 V
(“Reference
waveform No.23: ”) Ignition switch turned ON
with barometric pressure
at 100 kPa, 760 mmHg.
—
0.4 – 2.0 V
(“Reference
waveform No.24: ”) While engine running at
specified idle speed after
warmed up with
barometric pressure at
100 kPa, 760 mmHg.
C37-54 GRN TP sensor (main)
signal 0.75 – 1.08 V
Ignition switch turned ON
and accelerator pedal at
idle position after warmed
up engine.
—
3.67 – 4.24 V Ignition switch turned ON
and accelerator pedal at
full depressed position
after warmed up engine.
C37-55 ORN Ground for sensors Below 0.3 V Ignition switch turned ON. —
C37-56 RED Knock sensor
signal 2 – 3 V
(“Reference
waveform No.25: ” and “Reference
waveform No.26: ”) Ignition switch turned ON.
—
Engine running at 4000 r/
min. after warmed up.
C37-57 YEL Ground for sensors Below 0.3 V Ignition switch turned ON. —
C37-58 BLK/
ORN Ground for ECM Below 0.3 V Ignition switch turned ON.
—
C37-59 YEL/
GRN Oil control valve
ground
Below 1.3 V Ignition switch turned ON.
—
C37-60 YEL/
RED Oil control valve
output *0 – 0.6 V
↑↓
10 – 14 V
(“Reference
waveform No.27: ” and “Reference
waveform No.28: ”) At the moment of ignition
switch turned ON.
Output signal is active
high pulse. Duty ratio
varies depending on
vehicle condition.
Terminal
No. Wire
color Circuit Normal voltage
ConditionRemarks
Terminal
No. Wire
color Circuit Normal voltage Condition Remarks
E23-1 BLK/
RED Main power supply 10 – 14 V Ignition switch turned ON. —
E23-2 WHT/
RED Power source for
ECM internal
memory
10 – 14 V Ignition switch turned ON. —
E23-3 RED CAN (high)
communication line
(active high signal)
for ABS control
module, BCM,
combination meter *2.5 – 4.5 V
(“Reference
waveform No.29: ”) Ignition switch turned ON
with engine at stop. CAN communication line
signal is pulse. Pulse
signal displayed with a
regular frequency with
varies depending on
engine condition.

Downloaded from www.Manualslib.com manuals search engine 1A-182 Engine General Information and Diagnosis:
E23-25 PPLVehicle speed
signal output for P/
S control module *0 – 1 V
↑↓
10 – 14 V
(“Reference
waveform No.32: ”) Vehicle running. Sensor signal is pulse.
Pulse frequency varies
depending on vehicle
speed.
(21 pulses are generated
per sec. at 30 km/h, 19
mph.) (2561 pulses/km)
E23-26 RED/
BLU EPS signal 10 – 14 V Ignition switch turned ON.
—
0 – 1 V With engine running at idle
speed, and steering wheel
turned to the right or left as
far as it stops.
E23-27 — — — — —
E23-28 YEL/
BLK Serial
communication line
for immobilizer coil
antenna
10 – 14 V Ignition switch turned ON. —
E23-29 BLK/
WHT Ignition switch
signal 0 – 1 V Ignition switch turned OFF.
—
10 – 14 V Ignition switch turned ON.
E23-30 WHT Starting motor
control relay output 0 – 1 V Ignition switch turned ON.
—
0 – 1 V Ignition switch is turned to
ST (engine cranking)
position.
E23-31 BLK Ground for ECM Below 0.3 V Ignition switch turned ON. —
E23-32 RED/
YEL Power supply of
throttle actuator
drive circuit
10 – 14 V Ignition switch turned ON. —
E23-33 — — — — —
E23-34 RED Output for 5 V
power source of
APP sensor (sub) 4.5 – 5.5 V Ignition switch turned ON. —
E23-35 BRN Output for 5 V
power source of
APP sensor (main) 4.5 – 5.5 V Ignition switch turned ON. —
E23-36 YEL APP sensor (sub)
signal 1.55 – 1.65 V
Ignition switch turned ON
and accelerator pedal at
idle position after warmed
up engine.
—
4.18 – 5.12 V Ignition switch turned ON
and accelerator pedal at
full depressed position
after warmed up engine.
E23-37 YEL APP sensor (main)
signal 0.75 – 0.85 V
Ignition switch turned ON
and accelerator pedal at
idle position after warmed
up engine.
—
3.46 – 4.24 V Ignition switch turned ON
and accelerator pedal at
full depressed position
after warmed up engine.
E23-38 — — — — —
E23-39 — — — — —
E23-40 — — — — —
E23-41 — — — — —
E23-42 — — — — —
E23-43 — — — — —
E23-44 — — — — —
Terminal
No. Wire
color Circuit Normal voltage Condition Remarks

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.