ECM ground circuit SUZUKI SWIFT 2006 2.G Service Owner's Guide

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-81
DTC P0118: Engine Coolant Temperature Circuit HighS7RS0B1104028
Wiring Diagram
Refer to “DTC P0116: Engine Coolant Temperature Circuit Range / Performance”.
DTC Detecting Condition and Trouble Area
NOTE
When DTC P0108 and P0113 are indicated together, it is possible that “ORN” wire circuit 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. or more.
4) 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
ECT sensor output voltage is higher than 4.85 V for 0.5 seconds
continuously.
(Low engine coolant temperature (high voltage/high resistance))
(1 driving cycle detection logic) • ECT sensor circuit
• ECT 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 ECT sensor and its circuit check
1) Connect scan tool with i gnition switch turned OFF.
2) Turn ON ignition switch.
3) Check engine coolant 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”.
3 ECT voltage check
1) Disconnect connector from ECT sensor with ignition
switch turned OFF.
2) Check for proper connection to ECT sensor at “LT GRN” and “ORN” wire terminals.
3) If OK, then turn ON igniti on switch, measure voltage
between “LT GRN” wire terminal of ECT sensor
connector and vehicle body ground.
Is voltage about 4 – 6 V? Go to Step 6. Go to Step 4.
I4RS0A110026-01

Downloaded from www.Manualslib.com manuals search engine 1A-82 Engine General Information and Diagnosis:
4ECM voltage check
1) Turn OFF ignition switch.
2) Remove ECM from its br acket with ECM connectors
connected.
3) Check for proper connection of ECM connector at “C37- 24” terminal.
4) If OK, then turn ON igniti on switch, measure voltage
between “C37-24” wire terminal of ECM connector and
vehicle body ground.
Is voltage about 4 – 6 V? “LT GRN” wire is open
circuit. If wire and
connection are OK, go
to Step 5.
Go to Step 5.
5 ECT sensor harness voltage check
1) Disconnect connectors from ECM with ignition switch
turned OFF.
2) Turn ON ignition switch.
3) Measure voltage between “LT GRN” wire terminal of ECT sensor connector and vehicle body ground.
Is voltage about 0 V? Go to Step 6. “LT GRN” wire is
shorted to other circuit.
If wire is OK, substitute
a known-good ECM and
recheck.
6 ECT sensor harness resistance check
1) Measure resistance between “C37-24” terminal of ECM
connector and “LT GRN” wire terminal of ECT sensor
connector with ignition switch turn OFF.
Is resistance below 5
Ω? Go to Step 7. “LT GRN” wire is high
resistance circuit.
7 ECT sensor ground circuit check
1) Connect connectors to ECM.
2) Check for proper connection of ECT sensor connector at
“ORN” wire terminal.
3) Measure resistance between “ORN” wire terminal of ECT sensor connector and vehicle body ground.
Is resistance below 5
Ω? Go to Step 9. Go to Step 8.
8 ECT sensor ground circuit check
1) Measure resistance between “C37-55” terminal of ECM
connector and vehicle body ground.
Is resistance below 5
Ω? “ORN” wire is open
circuit or high resistance
circuit. Poor “C37-55”
connection.
Faulty ECM ground
circuit. If circuit is OK,
substitute a known-
good ECM and recheck.
9 ECT sensor for performance check
1) Check ECT sensor according to “ECT Sensor Inspection
in Section 1C”.
Is it in good condition? Substitute a known-
good ECM and recheck.
Replace ECT sensor.
Step Action Yes No

Downloaded from www.Manualslib.com manuals search engine 1A-84 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 TP sensor and its circuit check
1) Connect scan tool to DLC with ignition switch turned
OFF.
2) Turn ON ignition switch, check “TP Sensor 1 Volt” displayed on scan tool when accelerator pedal is idle
position and fully depressed.
Is displayed TP sensor value as described voltage in “Scan
Tool Data:”? Intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection
Inspection in Section
00”.
Go to Step 3.
3 ECM voltage check
1) Disconnect connector from electric throttle body with
ignition switch turned OFF.
2) Check for proper connection to electric throttle body at “RED”, “GRN” and “BLK” wire terminals.
3) If OK, measure voltage between “RED” wire terminal of electric throttle body connector and engine ground with
ignition switch turned ON.
Is voltage 4 – 6 V? Go to Step 6.
Go to Step 4.
4 ECM voltage check
1) Turn OFF ignition switch.
2) Remove ECM from its br acket with ECM connectors
connected.
3) Check for proper connection of ECM connector at “C37- 43” terminal.
4) If OK, measure voltage between “C37-43” terminal of ECM connector and engine ground with ignition switch
turned ON.
Is voltage 4 – 6 V? “RED” wire is open or
high resistance circuit.
Go to Step 5.
5 Wire harness check
1) Disconnect connectors from ECM with ignition switch
turned OFF.
2) Measure resistance between “C37-43” terminal of ECM connector and engine ground.
Is resistance infinity? Substitute a known-
good ECM and check.
“RED” wire is shorted to
ground circuit.
"GRN"
"RED"
"WHT"
"BLK"
"LT GRN/BLK"
"LT GRN/RED"
I4RS0B110022-02

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-85
DTC P0123: Throttle / Pedal Position Sensor / Switch “A” (Main) Circuit HighS7RS0B1104030
Wiring Diagram
Refer to “DTC P0122: Throttle / Pedal Position Sensor / Switch “A” (Main) Circuit Low”.
DTC Detecting Condition and Trouble Area
NOTE
When DTC P0123 and P0223 are indicated together, it is possible that “RED” wire shorted to power
circuit and/or “BLK” wire 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) Keep the accelerator pedal at idle position for 2 seconds.
4) Keep the accelerator pedal at fully depressed position for 2 seconds.
5) Repeat Step 3) and 4) for 3 times.
6) Check DTC. 6
Wire harness check
1) Measure voltage between “GRN” wire terminal of electric
throttle body connector and engine ground with ignition
switch turned ON.
Is voltage 4 – 6 V? Go to Step 9. Go to Step 7.
7 Wire harness check
1) Disconnect connectors from ECM with ignition switch
turned OFF.
2) Check for proper connection of ECM connector at “C37- 54” and “C37-42” terminals.
3) If OK, measure resistance between “GRN” and “BLK” wire terminals of electric throttle body connector.
Is resistance infinity? Go to Step 8. “GRN” wire is shorted to
“BLK” wire.
8 Wire harness check
1) Measure resistance between “GRN” wire terminal of
electric throttle body connector and engine ground with
ignition switch turned OFF.
Is resistance infinity? Substitute a known-
good ECM and recheck.
“GRN” wire is shorted to
ground circuit.
9 Electric throttle body check
1) Check TP sensor referring to “Throttle Position Sensor
Performance Check” under “Electric Throttle Body
Assembly On-Vehicle Inspection in Section 1C”.
Is output voltage within specified value? Substitute a known-
good ECM and recheck.
Replace electric throttle
body.
Step Action Yes No
DTC detecting condition
Trouble area
Output voltage of TP sensor (main) is more than specified
value for specified time continuously.
(1 driving detection logic) • TP sensor (main) circuit
• Electric throttle body assembly
•ECM

Downloaded from www.Manualslib.com manuals search engine 1A-86 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 TP sensor and its circuit check
1) Connect scan tool to DLC with ignition switch turned
OFF.
2) Turn ON ignition switch, check “TP Sensor 1 Volt” displayed on scan tool when accelerator pedal is idle
position and fully depressed.
Is displayed TP sensor value as described voltage in “Scan
To o l D a t a ” ? Intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection
Inspection in Section
00”.
Go to Step 3.
3 ECM voltage check
1) Disconnect connector from electric throttle body with
ignition switch turned OFF.
2) Check for proper connection to electric throttle body at “RED”, “GRN” and “BLK” wire terminals.
3) If OK, measure voltage between “RED” wire terminal of electric throttle body connector and engine ground with
ignition switch turned ON.
Is voltage 4 – 6 V? Go to Step 5.
Go to Step 4.
4 Wire harness check
1) Disconnect connectors from ECM with ignition switch
turned OFF.
2) Check for proper connection of ECM connector at “C37- 43” terminal.
3) Measured voltage between “C37-43” terminal of ECM connector and engine ground with ignition switch turned
ON.
Is voltage 0 V? Substitute a known-
good ECM and recheck.
“RED” wire is shorted to
power circuit.
5 Wire harness check
1) Measure voltage between “GRN” wire terminal of electric
throttle body connector and engine ground with ignition
switch turned ON.
Is voltage 4 – 6 V? Go to Step 9.
Go to Step 6.
"GRN"
"RED"
"WHT"
"BLK"
"LT GRN/BLK"
"LT GRN/RED"
I4RS0B110022-02

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-87
6Wire harness check
1) Turn OFF ignition switch.
2) Remove ECM from its br acket with ECM connectors
connected.
3) Check for proper connection of ECM connector at “C37- 43” and “C37-54” terminals.
4) If OK, measure voltage between “C37-54” terminal of ECM connector and engine ground with ignition switch
turned ON.
Is voltage 4 -6 V? “GRN” wire is open or
high resistance circuit.
Go to Step 7.
7 Wire harness check
1) Disconnect connectors from ECM with ignition switch
turned OFF.
2) Measure resistance between “GRN” and “RED” wire terminals of electric th rottle body connector.
Is resistance infinity? Go to Step 8. “GRN” wire is shorted to
“RED” wire.
8 Wire harness check
1) Turn ON ignition switch.
2) Measure voltage between “C37-54” terminal of ECM
connector and engine ground.
Is voltage 0 V? Substitute a known-
good ECM and recheck.
“GRN” wire is shorted to
power circuit.
9 Ground circuit check
1) Turn OFF ignition switch.
2) Measure resistance between “BLK” wire terminal of
electric throttle body connector and engine ground.
Is resistance below 5
Ω? Go to Step 11. Go to Step 10.
10 Ground circuit check
1) Remove ECM from its br acket with ECM connectors
connected.
2) Check for proper connection of ECM connector at “C37- 42” terminal.
3) Measure resistance between “C37-42” terminal of ECM connector and engine ground with ignition switch turned
OFF.
Is resistance below 5
Ω? “BLK” wire is open or
high resistance circuit.
Faulty ECM ground
circuit. If circuit is OK,
substitute a known-
good ECM and recheck.
11 Electric throttle body check
1) Check TP sensor referring to “Throttle Position Sensor
Performance Check” under “Electric Throttle Body
Assembly On-Vehicle Inspection in Section 1C”.
Is output voltage within specified value? Substitute a known-
good ECM and recheck.
Replace electric throttle
body.
Step Action Yes No

Downloaded from www.Manualslib.com manuals search engine 1A-90 Engine General Information and Diagnosis:
4HO2S-1 ground check
1) Disconnect connector from HO 2S-1 with ignition switch
turned OFF.
2) Check for proper connection to HO2S-1 connector at “BLK/RED”, “WHT”, “BLK /WHT” and “YEL” wire
terminals.
3) If connections are OK, m easure resistance between
“YEL” wire terminal of HO2S-1 connector and engine
ground.
Is measured resistance less than 5
Ω? Go to Step 5. “YEL” wire is open or
high resistance circuit.
Poor “C37-57” terminal
connection. Faulty ECM
ground.
If they are OK,
substitute a known-
good ECM and recheck.
5 Wire circuit check
1) Turn OFF ignition switch.
2) Remove ECM from its br acket with ECM connectors
connected.
3) Measure resistance between “WHT” wire terminal of HO2S-1 connector and “C37-10” terminal of ECM
connector.
Is resistance less than 5
Ω? Go to Step 6. “WHT” wire is high
resistance circuit or
open circuit. Poor “C37-
10” terminal connection.
Faulty ECM ground. If
they are OK, substitute
a known-good ECM and
recheck.
6 Wire circuit check
1) Disconnect connectors from ECM with ignition switch
turn OFF.
2) Measure resistance between “WHT” wire terminal of HO2S-1 connector and vehicle body ground.
Is resistance infinity? Go to Step 7. “WHT” wire is shorted to
ground circuit.
7 HO2S-1 signal circuit check
1) Measure voltage between “WHT” wire terminal of HO2S-
1 connector and vehicle body ground.
Is voltage 0 V? Go to Step 8. “WHT” wire is shorted to
other circuit.
8 HO2S-1 heater circuit check
1) Check HO2S-1 heater circuit referring to “DTC P0031 /
P0032: HO2S Heater Control Circuit Low / High
(Sensor-1)”.
Is circuit in good condition? Go to Step 9. Repair HO2S-1 circuit.
9 Exhaust system check
1) Check exhaust system for exhaust gas leakage.
Is it OK? Go to Step 4 in “DTC
P0171 / P0172: Fuel
System Too Lean /
Rich”.
If it is in good condition,
go to Step 10.Repair leakage of
exhaust system.
10 Air intake system check
1) Check air intake system for clog or leak.
Is it OK? Check HO2S-1 referring
to “HO2S-1 and HO2S-
2 Heater On-Vehicle
Inspection in Section
1C”.
If it is in good condition,
substitute a known-
good ECM and recheck.Repair or replace air
intake system.
Step Action Yes No

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-93
2HO2S-1 output voltage check
1) Connect scan tool to DLC with ignition switch turned
OFF.
2) Warm up engine to normal operating temperature and keep it at 2000 r/min. for 60 sec.
3) Repeat racing engine (Repeat depressing accelerator pedal 5 to 6 times continuous ly to enrich A/F mixture and
take foot off from pedal to enlean it) and check HO2S
output voltages displayed on scan tool.
Is over 0.6 V and below 0.3 V indicated? Intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection
Inspection in Section
00”. If check result is
OK, go to Step 3.
Go to Step 3.
3 HO2S-1 ground check
1) Disconnect connector from HO 2S-1 with ignition switch
turned OFF.
2) Check for proper connection to HO2S-1 at “BLK/RED”, “WHT”, “BLK/WHT” and “YEL” wire terminals.
3) If wire and connection are OK, measure resistance between “YEL” wire terminal of HO2S-1 connector and
engine ground.
Is resistance less than 5
Ω? Go to Step 4. “YEL” wire is open or
high resistance circuit.
Poor “C37-57” terminal
connection. Faulty ECM
ground.
If they are OK,
substitute a known-
good ECM and recheck.
4 Wire circuit check
1) Turn OFF ignition switch.
2) Remove ECM from its br acket with ECM connectors
connected.
3) Measure resistance between “WHT” wire terminal of HO2S-1 connector and “C37-10” terminal of ECM
connector.
Is resistance less than 5
Ω? Go to Step 5. “WHT” wire is high
resistance circuit or
open circuit. Poor “C37-
10” terminal connection
of ECM connector.
Faulty ECM ground. If
they are OK, substitute
a known-good ECM and
recheck.
5 Wire circuit check
1) Disconnect connectors from ECM with ignition switch
turned OFF.
2) Measure resistance between “WHT” wire terminal of HO2S-1 connector and vehicle body ground.
Is resistance infinity? Go to Step 6. “WHT” wire is shorted to
ground circuit.
6 HO2S-1 heater circuit check
1) Check HO2S-1 heater circuit referring to “DTC P0031 /
P0032: HO2S Heater Control Circuit Low / High
(Sensor-1)”.
Is it in good condition? Go to Step 7. Repair HO2S-1 circuit.
7 Exhaust system check
1) Check exhaust system for exhaust gas leakage.
Is it OK? Go to Step 4 in “DTC
P0171 / P0172: Fuel
System Too Lean /
Rich”.
If it is in good condition,
go to Step 8.Repair leakage of
exhaust system.
8 Air intake system check
1) Check air intake system for clog or leak.
Is it OK? Check HO2S-1 referring
to “HO2S-1 and HO2S-
2 Heater On-Vehicle
Inspection in Section
1C”.
If it is in good condition,
substitute a known-
good ECM and recheck.Repair or replace air
intake system.
Step Action Yes No

Downloaded from www.Manualslib.com manuals search engine 1A-96 Engine General Information and Diagnosis:
4HO2S-2 ground check
1) Disconnect connector from HO 2S-2 with ignition switch
turned OFF.
2) Check for proper connection to HO2S-2 connector at “RED/BLU”, “BRN”, “YEL” and “BLK/WHT” wire
terminals.
3) If connections are OK, m easure resistance between
“YEL” wire terminal of HO2S-2 connector and engine
ground.
Is resistance less than 5
Ω? Go to Step 5. “YEL” wire is open or
high resistance circuit.
Poor “C37-57” terminal
connection. Faulty ECM
ground.
If they are OK,
substitute a known-
good ECM and recheck.
5 Wire circuit check
1) Turn OFF ignition switch.
2) Remove ECM from its br acket with ECM connectors
connected.
3) Measure resistance between “BRN” wire terminal of HO2S-2 connector and “C37-11” terminal of ECM
connector.
Is resistance less than 5
Ω? Go to Step 6. “BRN” wire is high
resistance circuit or
open circuit. Poor “C37-
11” terminal connection.
If they are OK,
substitute a known-
good ECM and recheck.
6 Wire circuit check
1) Disconnect connectors from ECM with ignition switch
turned OFF.
2) Measure resistance between “BRN” wire terminal of HO2S-2 connector and vehicle body ground.
Is resistance infinity? Go to Step 7. “BRN” wire is shorted to
ground circuit.
7 HO2S-2 signal circuit check
1) Measure voltage between “BRN” wire terminal of HO2S-
2 connector and vehicle body ground.
Is voltage 0 V? Go to Step 8. “BRN” wire is shorted to
other circuit.
8 HO2S-2 heater circuit check
1) Check HO2S-2 heater circuit referring to “DTC P0037 /
P0038: HO2S Heater Control Circuit Low / High
(Sensor-2)”.
Is circuit in good condition? Go to Step 9. Repair HO2S-2 circuit.
9 Exhaust system check
1) Check exhaust system for exhaust gas leakage.
Is it OK? Go to Step 4 in “DTC
P0171 / P0172: Fuel
System Too Lean /
Rich”.
If it is in good condition,
go to Step 10.Repair leakage of
exhaust system.
10 Air intake system check
1) Check air intake system for clog or leak.
Is it OK? Check HO2S-2 referring
to “HO2S-1 and HO2S-
2 Heater On-Vehicle
Inspection in Section
1C”.
If it is in good condition,
substitute a known-
good ECM and recheck.Repair or replace air
intake system.
Step Action Yes No

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-97
DTC P0140: O2 Sensor (HO2S) Circuit No Activity Detected (Sensor-2)S7RS0B1104035
Wiring Diagram
Refer to “DTC P0137 / P0138: O2 Sensor (HO2S) Circuit Low Voltage / High Voltage (Sensor-2)”
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.

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) Increase vehicle speed to 60 – 80 km/h (37 – 50 mile/h) at 5th gear or D range.
5) Release accelerator pedal and with engine brake applied, ke ep vehicle coasting (with fuel cut for 4 sec. or more),
then stop vehicle and run engine at idle speed for 60 sec. or more.
6) 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
HO2S-2 voltage is higher than specified value after warming up engine
(circuit open).
(2 driving cycle detection logic) •HO2S-2
• HO2S-2 circuit
•ECM
• Exhaust gas leakage
• Air intake system
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 HO2S-2 ground check
1) Disconnect connector from HO 2S-2 with ignition switch
turned OFF.
2) Check for proper connection to HO2S-2 connector at “RED/BLU”, “BRN”, “YEL” and “BLK/WHT” wire
terminals.
3) If connections are OK, m easure resistance between
“YEL” wire terminal of HO2S-2 connector and engine
ground.
Is resistance less than 5
Ω? Go to Step 3. “YEL” wire is open or
high resistance circuit.
Poor “C37-57” terminal
connection. Faulty ECM
ground.
If they are OK,
substitute a known-
good ECM and recheck.