2006 SUZUKI SWIFT ECM ground circuit

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.

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-215
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

Downloaded from www.Manualslib.com manuals search engine Aux. Emission Control Devices: 1B-2
EVAP Canister Purge Valve and Its Circuit
Inspection
S7RS0B1206002
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.

1) Prepare to operate EVAP canister purge valve as follows.
a) When using SUZUKI scan tool:
i) Connect SUZUKI scan tool to DLC (1) with ignition switch turned OFF and disconnect
purge valve vacuum hoses from intake
manifold and EVAP canister.
ii) Turn ON ignition switch, clear DTC and select “MISC TEST” mode on SUZUKI scan
tool.
Special tool
(A): SUZUKI scan tool b) When not using SUZUKI scan tool:
NOTE
Before performed this check, be sure to read
the “Precautions of ECM Circuit Inspection in
Section 1A”.

i) Disconnect purge valve vacuum hoses from
intake manifold and EVAP canister.
ii) Remove ECM from it s bracket referring to
“ECM Removal and Inst allation in Section
1C”.
iii) Connect special tool between ECM and ECM connector referring to “Inspection of ECM
and Its Circuits in Section 1A”
iv) Turn ON ignition switch. Using service wire, ground “C37-29” terminal
circuit of special tool (valve ON: “B”) and
unground it (valve OFF: “A”).
2) Check purge valve for operation and vacuum passage for clog when valve is switched ON and
OFF by using SUZUKI scan tool or service wire.
If check result is not satisfactory, check vacuum
hoses, EVAP canister purge valve, wire harness and
connections.
EVAP canister purge valve specification
[A] Valve OFF: When vacuum (–60 kPa (–8.7 psi))
is applied to hose (1), vacuum can be applied.
[B] Valve ON: When vacuum is applied to hose
(1), vacuum can not be applied.
Special tool
(A): 09917–47011
(A)
1
I4RS0B120003-03
“C37-29”“A”
“B”
I4RS0B120006-02
[A] [B]
1
(A)1
(A)
I3RB0A120005-02

Downloaded from www.Manualslib.com manuals search engine Engine Electrical Devices: 1C-11
MAF and IAT Sensor On-Vehicle InspectionS7RS0B1306018
NOTE
Before performed this inspection, be sure to
read the “Precautions of ECM Circuit
Inspection in Section 1A”.

1) Disconnect negative (–) cable at battery.
2) Disconnect MAF and IAT sensor connector.
3) Connect voltmeter to “BLK/RED” wire terminal (2) of
MAF and IAT sensor connector (1) disconnected and
ground.
4) Turn ON ignition switch position and check that voltage is battery voltage.
If not, check if wire harness is open or connection is
poor.
5) Turn OFF ignition switch position and connect connector to MAF and IAT sensor.
6) Remove ECM from its bracket referring to “ECM Removal and Installation”.
7) Connect special tool between ECM and ECM connector referring to “Inspection of ECM and Its
Circuits in Section 1A”.
8) Turn ON ignition switch position and check MAF signal voltage between “C37-26” terminal circuit and
“C37-27” terminal circuit of special tool.
MAF signal voltage between “C37-26” terminal
circuit and “C37-27” termi nal circuit of special
tool
MAF signal voltage of MAF and IAT sensor with
ignition switch turned ON: 0.5 – 1.0 V
9) Start engine and check that voltage is lower than 5 V and it rises as engine speed increases.
MAF signal voltage between “C37-26” terminal
circuit and “C37-27” termi nal circuit of special
tool
MAF signal reference voltage of MAF and IAT
sensor at specified Idle speed: 1.3 – 1.8 V 10) If check result is not as
specified above, cause may
lie in wire harness, connec tor connection, MAF and
IAT sensor or ECM.
MAF and IAT Sensor Removal and InstallationS7RS0B1306019
CAUTION!
• Do not disassemble MAF and IAT sensor.
• Do not expose MAF and IAT sensor to any shock.
• Do not clean MAF and IAT sensor.
• If MAF and IAT sensor has been dropped, it should be replaced.
• Do not blow compressed air by using air gun or the like.
• Do not put finger or any other object into MAF and IAT sensor. Malfunction may
occur.

Removal
1) Disconnect negative (–) cable at battery.
2) Disconnect MAF and IAT sensor connector.
3) Remove air cleaner case (1).
4) Remove MAF and IAT sensor (2) from air cleaner case.
Installation
Reverse removal procedure noting the followings.
• Tighten MAF and IAT sensor screws to specified torque.
Tightening torque
MAF and IAT sensor screw (a): 1.5 N·m (0.15 kgf-
m, 1.1 lb-ft)
• Connect MAF and IAT sensor connector securely.
1. ECM
I3RB0A130009-01
“C37-27” “C37-26” 1
I4RS0A130009-01
1
2
I4RS0A130010-01
(a)
I4RS0A130011-01

Downloaded from www.Manualslib.com manuals search engine Engine Electrical Devices: 1C-13
Without Using SUZUKI Scan Tool1) Measure sensor voltage between “C37-23” terminal of ECM connector and vehicle body ground referring
to “Inspection of ECM and Its Circuits in Section 1A”.
If check result is satisfactory, electric load current
sensor is in good condition.
If check result is not satisfactory, check the following
parts and circuit.
• Electric load current sensor circuit (power, ground and output)
• Following charging system components – Battery (refer to “Battery Inspection in Section
1J”)
– Generator (refer to “Generator Inspection in Section 1J”)
– Generator output control circuit (refer to “Generator Test (Undercharged Battery Check)
in Section 1J”)
– Generator field coil monitor circuit (refer to “Generator Inspection in Section 1J”) If electric load current sensor circuit and charging
system is in good condition,
electric load current sensor
(1) is faulty.
Specifications
Tightening Torque SpecificationsS7RS0B1307001
Reference:
For the tightening torque of fastener not specified in this section, refer to “Fasteners Information in Section 0A”.
2. Main fuse box
2
1
I5RS0C130001-01
Fastening part
Tightening torque
Note
N ⋅mkgf-mlb-ft
ECM mounting bolt 8 0.8 6.0 )
APP sensor assembly nut 5.5 0.55 4.0 )
ECT sensor 15 1.5 11.0 )
Heated oxygen sensor 45 4.5 32.5 )
CMP sensor bolt 10 1.0 7.5 )
CKP sensor bolt 10 1.0 7.5 )
Knock sensor 22 2.2 16.0 )
MAF and IAT sensor screw 1.5 0.15 1.1 )

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Diagnostic Information and Procedures
Engine Cooling Symptom DiagnosisS7RS0B1604001
ConditionPossible cause Correction / Reference Item
Engine overheats
(Radiator fan operates) Loose or broken water pump belt
Adjust or replace.
Not enough coolant Check coolant level and add as necessary.
Faulty thermostat Replace.
Faulty water pump Replace.
Dirty or bent radiator fins Clean or remedy.
Coolant leakage on cooling system Repair.
Clogged radiator Check and replace radiator as necessary.
Faulty radiator cap Replace.
Improper ignition timing Adjust.
Dragging brakes Adjust brake.
Slipping clutch Adjust or replace.
Poor charge battery Check and replace as necessary.
Poor generation generator Check and repair.
ECT sensor faulty Check and replace as necessary.
Radiator cooling fan relay No.2 and/or
No.3 faulty Check and replace as necessary.
Radiator fan motor faulty Check and replace as necessary.
ECM faulty Check and replace as necessary.
Wiring or grounding faulty Repair as necessary.
Equipped with too much electric load
part(s) Dismount.
Engine overheats
(Radiator fan does not
operate) Fuse blown
Check 30 A fuse of relay/fuse box and check
for short circuit to ground.
Radiator cooling fan relay No.1 faulty Check and replace as necessary.
ECT sensor faulty Check and replace as necessary.
Radiator cooling fan motor faulty Check and replace as necessary.
Wiring or grounding faulty Repair as necessary.
ECM faulty Check and replace as necessary.

Downloaded from www.Manualslib.com manuals search engine Ignition System: 1H-5
6Ignition coil assembly power supply and ground circuit
check
1) Check ignition coil assembly power supply and ground
circuits for open and short.
Are circuits in good condition? Go to Step 7.
Repair or replace.
7 Ignition coil assembly check
1) Check ignition coil for resistance referring to “Ignition
Coil Assembly (Including ignitor) Inspection”.
Is check result satisfactory? Go to Step 8.
Replace ignition coil
assembly.
8 CKP sensor check
1) Check CKP sensor referring to “CKP Sensor Inspection
in Section 1C”.
Is check result satisfactory? Go to Step 9.
Tighten CKP sensor
bolt, replace CKP
sensor or CKP sensor
plate.
9 CMP sensor check
1) Check CMP sensor referring to “Camshaft Position
(CMP) Sensor Inspection in Section 1C”.
Is check result satisfactory? Go to Step 10. Tighten CMP sensor
bolt, replace CMP
sensor or intake
camshaft.
10 Ignition trigger signal circuit check
1) Check ignition trigger signal wire for open, short and
poor connection.
Is circuit in good condition? Go to Step 11. Repair or replace.
11 A known-good ignition coil assembly substitution
1) Substitute a known-good ignition coil assembly and then
repeat Step 2.
Is check result of Step 2 satisfactory? Go to Step 12. Substitute a known-
good ECM and then
repeat Step 2.
12 Knock sensor check
1) Confirm that knock sensor circuit is in good condition
referring to “DTC P0327 / P0328: Knock Sensor 1 Circuit
Low / High in Section 1A”.
2) Check oscilloscope waveform of knock sensor signal
referring to “Reference waveform No.25” and
“Reference waveform No.26” under “Inspection of ECM
and Its Circuits in Section 1A”.
Is check result satisfactory? Go to Step 13. Substitute a known-
good knock sensor and
recheck.
13 Ignition timing check
1) Check initial ignition timing and ignition timing advance
referring to “Ignition Timing Inspection”.
Is check result satisfactory? System is in good
condition.
Check CMP sensor,
CMP sensor rotor tooth
of camshaft, CKP
sensor, CKP sensor
plate and/or input
signals related to this
system.
Step
Action YesNo

Downloaded from www.Manualslib.com manuals search engine 1I-1 Starting System:
Engine
Starting System
Schematic and Routing Diagram
Cranking System Circuit DiagramS7RS0B1902001
Diagnostic Information and Procedures
Cranking System Symptom DiagnosisS7RS0B1904001
Possible symptoms due to starting system trouble would be as follows:
• Starting motor does not run (or runs slowly)
• Starting motor runs but fails to crank engine
• Abnormal noise is heard
Proper diagnosis must be made to determine exactly where the cause of each trouble lies in battery, wiring harness,
(including starting motor switch), starting motor or engine.
Do not remove motor just because starting motor does not run. Check the following items and narrow down scope of
possible causes.
1) Condition of trouble
2) Tightness of battery terminals (including ground cable connection on engine side) and starting motor terminals
3) Discharge of battery
4) Mounting of starting motor
I4RS0A190001-01
1. Pinion drive lever 6. Magnetic switch contacts 11. Ignition & Starter switch
2. Pinion & Over-running clutch 7. Pull-in coil 12. Battery
3. Magnetic switch 8. Starting motor 13. To ECM
4. Hold-in coil 9. Starting motor control relay
5. Plunger 10. A/T: Transmission range switch (shift lever switch)