Vehicle speed signal SUZUKI SWIFT 2008 2.G Service User Guide

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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 temperature: 70 °C (158 °F) to 150 °C (302 °F)
• Altitude (barometric pressure): 2400 m, 8000 ft or less (560 mmHg, 75 kPa or more)

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) Drive vehicle at 40 mph (60 km/h) or higher. (engine speed: 2500 – 3000 r/min.)
5) Keep above vehicle speed for 6 min. or more. (Throt tle valve opening is kept constant in this step.)
6) Release accelerator pedal and with engine brake applied, keep vehicle coasting (with fuel cut for 3 sec. or more)
and then stop vehicle.
7) 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.

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 Is there DTC(s) other than HO2S-1? Go to applicable DTC
diag. flow.Go to Step 3.
3 HO2S-1 signal 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).
Does HO2S-1 output voltage deflect between below 0.3 V
and over 0.6 V repeatedly? Intermittent trouble.
Check for intermittent
referring to “Intermittent
and Poor Connection
Inspection in Section
00”. If check result is
OK, go to Step 9.
Go to Step 4.

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-91
DTC P0133: O2 Sensor (HO2S) Circuit Slow Response (Sensor-1)S7RS0B1104032
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 temperature: 70 °C (158 °F) to 150 °C (302 °F)
• Altitude (barometric pressure): 2400 m, 8000 ft or less (560 mmHg, 75 kPa or more)

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) Drive vehicle at 40 mph (60 km/h) or higher. (engine speed: 2500 – 3000 r/min.)
5) Keep above vehicle speed for 6 min. or more. (Throt tle valve opening is kept constant in this step.)
6) Release accelerator pedal and with engine brake applied, keep vehicle coasting (with fuel cut for 3 sec. or more)
and then stop vehicle.
7) Check if DTC and pending DTC exist by using scan tool. If not, check if oxygen sensor monitoring test has been
completed by using scan tool. If not in both of above c hecks (i.e., no DTC and pending DTC and oxygen sensor
monitoring test not completed), check vehicle cond ition (environmental) and repeat Step 3) through 6).
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 time (time to change from lean to rich or from rich to lean) of HO2S-1 output
voltage is about 1 sec. at minimum or aver age time of 1 cycle is 5 sec. at minimum.
(*2 driving cycle detection logic, monitoring once per driving cycle) Heated oxygen sensor-1
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 Is there DTC(s) other than HO2S-1 (DTC P0133)? Go to applicable DTC
diag. flow.Replace HO2S-1.

Downloaded from www.Manualslib.com manuals search engine 1A-92 Engine General Information and Diagnosis:
DTC P0134: O2 Sensor (HO2S) Circuit No Activity Detected (Sensor-1)S7RS0B1104033
Wiring Diagram
Refer to “DTC P0131 / P0132: O2 Sensor (HO2S) Circuit Low Voltage / High Voltage (Sensor-1)”
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 temperature: 70 °C (158 °F) to 150 °C (302 ° F)
• Altitude (barometric pressure): 2400 m, 8000 ft or less (560 mmHg, 75 kPa or more)

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) Drive vehicle at 40 mph (60 km/h) or higher. (engine speed: 2500 – 3000 r/min.)
5) Keep above vehicle speed for 6 min. or more. (Throt tle valve opening is kept constant in this step.)
6) Release accelerator pedal and with engine brake applied, keep vehicle coasting (with fuel cut for 3 sec. or more)
and then stop vehicle.
7) Check if DTC and pending DTC exist by using scan tool. If not, check if oxygen sensor monitoring test has been
completed by using scan tool. If not in both of above c hecks (i.e., no DTC and pending DTC and oxygen sensor
monitoring test not completed), check vehicle cond ition (environmental) and repeat Step 3) through 6).
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 voltage is higher than 0.6 V for more than 1 min
continuously after warming up engine or HO2S voltage is lower
than 0.3 V for more than 1 min continuously after warming up
engine.
(2 driving cycle detection logic) •HO2S-1
• HO2S-1 circuit
• Exhaust gas leakage
•ECM
• 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”.

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-95
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 temperature: 70 °C (158 °F) to 150 °C (302 °F)
• Altitude (barometric pressure): 2400 m, 8000 ft or less (560 mmHg, 75 kPa or more)

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 70 – 80 km/h (43 – 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) Repeat Step 4).
7) Keep above vehicle speed for 8 min. or more. (Throt tle valve opening is kept constant in this step.)
8) Repeat Step 5).
9) 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.

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 Is there DTC(s) other than fuel system (DTC P0171 / P0172)
and HO2S-2 (DTC P0140)? Go to applicable DTC
diag. flow.Go to Step 3.
3 HO2S-2 and its circuit 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).
Does HO2S-2 output voltage indicate deflection between
over 0.35 V and below 0.25 V? Go to “DTC P0171 /
P0172: Fuel System
Too Lean / Rich”.
Go to Step 4.

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.

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-105
DTC P0300 / P0301 / P0302 / P0303 / P0304: Random / Multiple Cylinder Misfire Detected / Cylinder 1
/ Cylinder 2 / Cylinder 3 / Cylinder 4 Misfire Detected
S7RS0B1104039
System Description
ECM measures the angle of the crankshaft based on the pulse signal from the CKP sensor and CMP sensor for each
cylinder. If it detects a large change in the angle speed of the crankshaft, it concludes occurrence of a misfire. When
the number of misfire is counted by ECM beyond the DTC de tecting condition, it determines the cylinder where the
misfire occurred and output it as DTC.
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.: –10 °C, 14 °F or higher
• Altitude (barometric pressure): 2400 m, 8000 ft or less (560 mmHg, 75 kPa or more)

1) With ignition switch turned OFF, connect scan tool.
2) Turn ON ignition switch and print Freeze Frame Data or write them down using scan tool.
3) Clear DTC using scan tool.
4) Drive vehicle under freeze frame data condition as noted for 1 min. or more.
5) Stop vehicle and check DTC and pending DTC. 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
DTC detecting condition
Trouble area
DTC P0300:
• Misfire, which causes catalyst to overheat during 200 engine revolutions, is detected at 2 or more cylinders. (MIL flashes as lo ng as this misfire occurs continuously.)
or
• Misfire, which affects exhaust emission adv ersely during 1000 engine revolution, is
detected at 2 or more cylinders. (2 driving cycle detection logic) • Ignition system
• Fuel injector and its circuit
• Fuel pressure
• EGR system
• Abnormal air drawn in
• Engine compression
• Valve lash adjuster
• Valve timing
• Fuel shortage
• Exhaust system
• Fuel of poor quality
DTC P0301, P0302, P0303, P0304:
• Misfire, which causes catalyst to overheat during 200 engine revolutions, is detected
at 1 cylinder. (MIL flashes as long as this misfire occurs continuously.)
or
• Misfire, which affects exhaust emission adv ersely during 1000 engine revolution, is
detected at 1 cylinder. (2 driving cycle detection logic)

Downloaded from www.Manualslib.com manuals search engine Engine General Information and Diagnosis: 1A-117
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 temperature: 70 °C (158 °F) to 150 °C (302 °F)
• Altitude (barometric pressure): 2400 m, 8000 ft or less (560 mmHg, 75 kPa or more)

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) Run engine at idle for 10 min.
5) Drive vehicle and increase engine speed 3000 rpm in 3rd gear.
6) Release accelerator pedal and with engine brake applied, keep vehicle coasting for 5 sec. or more. (Keep fuel cut condition for 5 sec. or more) If fuel cut condition is not ke pt for 5 sec. or more, coast down a slope in engine speed
1000 – 3000 rpm for 5 sec. or more.
7) Stop vehicle and run engine at idle.
8) Check DTC and pending DTC by using scan tool.
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
DTC P0401:
Difference in intake manifold absolute pressure between opened EGR valve
and closed EGR valve is smaller than specified value.
(*2 driving cycle detection logic, monitoring once per driving cycle)
DTC P0402:
Difference in intake manifold absolute pressure between opened EGR valve
and closed EGR valve is la rger than specified value.
(*2 driving cycle detection logic, monitoring once per driving cycle) •EGR valve
• EGR passage
• MAP 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 Do you have SUZUKI scan tool? Go to Step 3.Go to Step 5.

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 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.