6D2-2 IGNITION SYSTEM
General Description
Ignition is done by the Ignition Module that fires.
Since the cylinder on exhaust stroke requires less energy to
fire its spark plug, energy from the ignition coils can be utilized
to fire the mating cylinder on compression stroke.
A notch in the timing disc on the crankshaft activates the crank
angle sensor which then sends information such as firing order
and starting timing of ignition coil to the ECM.
By receiving signals such as crank position, engine speed,
water temperature and Manifold Absolute Pressure (MAP), the
ECM controls the ignition timing.
Service Precaution
CAUTION:
Always use the correct fastener in the proper location.
When you replace a fastener, use ONLY the exact part
number for that application. ISUZU will call out those
fasteners that require a replacement after removal. ISUZU
will also call out the fasteners that require thread lockers
or thread sealant. UNLESS OTHERWISE SPECIFIED, do
not use supplemental coatings (Paints, greases, or other
corrosion inhibitors) on threaded fasteners or fastener
joint interfaces. Generally, such coatings adversely affect
the fastener torque and the joint clamping force, and may
damage the fastener. When you install fasteners, use the
correct tightening sequence and specifications. Following
these instructions can help you avoid damage to parts
and systems.
Diagnosis
Refer to Section Drivability and Emissions for the diagnosis to
electronic ignition system (El system).
Ignition Coil
Removal
1. Disconnect battery ground cable.
2. Disconnect the Ignition coil connector.
3. Remove the ignition coil.
Installation
1. Install the ignition coil.
Connect ignition coil connector and ignition coil, then tighten
bolt to the specified torque.
Torque: 20 N
m (2.0 kgf
m)
2. Connect battery ground cable.
6D3-2 STARTING AND CHARGING SYSTEM
Starting System
General Description
Cranking Circuit
The cranking system consists of a battery, starter, starter
switch, starter relay, etc. These main components are
connected.
Starter
The cranking system employs a magnetic type reduction
starter in which the motor shaft is also used as a pinion shaft.
When the starter switch is turned on, the contacts of magnetic
switch are closed, and the armature rotates. At the same time,
the plunger is attracted, and the pinion is pushed forward by
the shift lever to mesh with the ring gear.
Then, the ring gear runs to start the engine. When the engine
starts and the starter switch is turned off, the plunger returns,
the pinion is disengaged from the ring gear, and the armature
stops rotation. When the engine speed is higher than the
pinion, the pinion idles, so that the armature is not driven.
Service Precaution
CAUTION:
Always use the correct fastener in the proper location.
When you replace a fastener, use ONLY the exact part
number for that application. ISUZU will call out those
fasteners that require a replacement after removal. ISUZU
will also call out the fasteners that require thread lockers
or thread sealant. UNLESS OTHERWISE SPECIFIED, do
not use supplemental coatings (Paints, greases, or other
corrosion inhibitors) on threaded fasteners or fastener
joint interfaces. Generally, such coatings adversely affect
the fastener torque and the joint clamping force, and may
damage the fastener. When you install fasteners, use the
correct tightening sequence and specifications. Following
these instructions can help you avoid damage to parts
and systems.
Diagnosis
Condition Possible cause Correction
Starter does not run Charging failure Repair charging system
Battery Failure Replace Battery
Terminal connection failure Repair or replace terminal connector
and/or wiring harness
Starter switch failure Repair or replace starter switch
Starter failure Repair or replace starter
ENGINE DRIVEABILITY AND EMISSIONS 6E–1
ENGINE
CONTENTS
C24SE ENGINE DRIVEABILITY AND EMISSIONS
ABBREVIATIONS CHARTS ......................... 6E-6
ECM Circuit Diagram (1/2) ............................ 6E-11
ECM Circuit Diagram (2/2) ............................ 6E-12
GROUND POINT CHART - LHD G.EXP (1/4) 6E-13
GROUND POINT CHART - RHD G.EXP (1/4) 6E-17
LOCATION ................................................... 6E-21
CABLE HARNESS & CONNECTOR
LOCATION .............................................. 6E-23
CABLE HARNESS & CONNECTOR
LOCATION LHD ................................... 6E-24
CABLE HARNESS & CONNECTOR
LOCATION RHD ................................... 6E-25
CONNECTOR LIST ...................................... 6E-28
RELAY AND FUSE ....................................... 6E-30
RELAY AND FUSE BOX LOCATION
(LHD & RHD) ........................................... 6E-30
FUSE AND RELAY LOCATION (LHD & RHD) 6E-32
ECM WIRING DIAGRAM (1/9) ..................... 6E-33
ECM WIRING DIAGRAM (2/9) ..................... 6E-34
ECM WIRING DIAGRAM (3/9) ..................... 6E-35
ECM WIRING DIAGRAM (4/9) ..................... 6E-36
ECM WIRING DIAGRAM (5/9) ..................... 6E-37
ECM WIRING DIAGRAM (6/9) ..................... 6E-38
ECM WIRING DIAGRAM (7/9) ..................... 6E-39
ECM WIRING DIAGRAM (8/9) ..................... 6E-40
ECM WIRING DIAGRAM (9/9) ..................... 6E-41
ECM CONNECTOR PIN ASSIGNMENT &
OUTPUT SIGNAL .................................... 6E-42
GENERAL DESCRIPTION FOR ECM AND
SENSORS ............................................... 6E-48
Engine Control Module (ECM) ................... 6E-48
Manifold Absolute Pressure (MAP) Sensor 6E-48
Throttle Position Sensor (TPS) .................. 6E-49
Idle Air Control (IAC) Valve ....................... 6E-49
Crankshaft Position (CKP) Sensor ............ 6E-50
Knock Sensor (KS) .................................... 6E-50
Engine Coolant Temperature (ECT) Sensor 6E-50
Intake Air Temperature (IAT) Sensor ........ 6E-51
Vehicle Speed Sensor (VSS) .................... 6E-51
Heated Ox ygen (O
2) Sensor ..................... 6E-51
GENERAL DESCRIPTION FOR FUEL
METERING .............................................. 6E-52Battery Voltage Correction Mode ............... 6E-52
Clear Flood Mode ...................................... 6E-52
Deceleration Fuel Cutoff (DFCO) Mode .... 6E-52
Engine Speed/ Vehicle Speed/ Fuel Disable
Mode ........................................................ 6E-52
Acceleration Mode ..................................... 6E-52
Fuel Cutoff Mode ....................................... 6E-52
Starting Mode ............................................ 6E-52
Run Mode .................................................. 6E-52
Fuel Metering System Components .......... 6E-53
Fuel Injector ............................................... 6E-53
Fuel Pressure Regulator ............................ 6E-53
Fuel Rail ..................................................... 6E-53
Fuel Pump Electrical Circuit ....................... 6E-53
Thottle Body Unit ....................................... 6E-53
GENERAL DESCRIPTION FOR ELECTRIC
IGNITION SYSTEM ................................. 6E-54
Spark Plug ................................................. 6E-54
GENERAL DESCRIPTION FOR EVAPORATIVE
EMISSION SYSTEM ............................... 6E-57
EVAP Emission Control System Purpose .. 6E-57
EVAP Emission Control System Operation 6E-57
System Fault Detection .............................. 6E-57
POSITIVE CRANKCASE VENTILATION (PCV)
SYSTEM .................................................. 6E-59
Crankcase Ventilation System Purpose .... 6E-59
A/C CLUTCH DIAGNOSIS ........................ 6E-60
A/C Clutch Circuit Operation ...................... 6E-60
A/C Clutch Circuit Purpose ........................ 6E-60
A/C Request Signal ................................... 6E-60
ISUZU STRATEGY BASED DIAGNOSTICS 6E-61
Overview .................................................... 6E-61
STRATEGY BASED DIAGNOSTICS CHART 6E-61
Diagnostic Thought Process ...................... 6E-62
1. Verify the Complaint .............................. 6E-62
2. Perform Preliminary Checks .................. 6E-62
3. Check Bulletins and Troubleshooting Hints 6E-63
4. Perform Service Manual Diagnostic Checks 6E-63
5a and 5b. Perform Service Manual Diagnostic
Procedures .............................................. 6E-63
5c. Technician Self Diagnoses .................. 6E-63
5d. Intermittent Diagnosis .......................... 6E-64
6E–120 ENGINE DRIVEABILITY AND EMISSIONS
connectors for backed-out terminals, improper
mating, broken locks, improperly formed or damaged
terminals, and poor terminal-to-wire connection.
If these codes are also set, it could indicate a
problem with the 5 Volt reference circuit.
Damaged harness - Inspect the wiring harness fordamage, short to ground, short to battery positive,
and open circuit. If the harness appears to be OK,
observe the MAP display on the Tech 2 while moving
connectors and wiring harnesses related to the
sensor. A change in the display will indicate the
location of the fault.
Diagnostic Trouble Code (DTC) P0107
Manifold Absolute Pressure Circuit Low Input
Step A ction Value(s) Yes No
1 Was the “On-Board Diagnostic (OBD) System Check”
performed?
—Go to Step 2Go to On Board
Diagnostic
(OBD) System
Check
2 1. Connect the Tech 2.
2. Review and record the failure information.
3. Select “F0: Read DTC Infor By Priority” in “F0:
Diagnostic Trouble Code”.
Is the DTC P0107 stored as “Present Failure”?—Go to Step 3Refer to
Diagnostic Aids
and Go to Step
3
3 1. Using the Tech2, ignition “On” and engine “Off”.
2. Select “Clear DTC Information” with the Tech2 and
clear the DTC information.
3. Operate the vehicle and monitor the “F5: Failed
This Ignition” in “F2: DTC Information”.
Was the DTC P0107 stored in this ignition cycle?—Go to Step 4Refer to
Diagnostic Aids
and Go to Step
4
4 Check for poor/faulty connection at the MAP sensor or
ECM connector. If a poor/faulty connection is found,
repair as necessary.
Was the problem found?
—Verify repair Go to Step 5
5 Visually check the MAP.
Was the problem found? —Go to Step 9 Go to Step 6
6 Using the DVM and check the MAP sensor power
supply circuit.
1. Ignition “On”, engine “Off”.
2. Disconnect the MAP sensor connector.
3. Check the circuit for open or short to ground
circuit.
Was the DVM indicated specified value?
Approx imately
5.0V Go to Step 8Go to Step 7
16
31 24E85 E60(J1)
V
E85
3
6E–132 ENGINE DRIVEABILITY AND EMISSIONS
terminals, and poor terminal-to-wire connection.
Damaged harness - Inspect the wiring harness for
damage, short to ground, short to battery positive,
and open circuit. If the harness appears to be OK,observe the IAT display on the Tech 2 while moving
connectors and wiring harnesses related to the IAT
sensor. A change in the IAT display will indicate the
location of the fault.
Diagnostic Trouble Code (DTC) P0113
Intake Air Temperature Sensor High Input
Step A ction Value(s) Yes No
1 Was the “On-Board Diagnostic (OBD) System Check”
performed?
—Go to Step 2Go to On Board
Diagnostic
(OBD) System
Check
2 1. Connect the Tech 2.
2. Review and record the failure information.
3. Select “F0: Read DTC Infor By Priority” in “F0:
Diagnostic Trouble Code”.
Is the DTC P0113 stored as “Present Failure”?—Go to Step 3Refer to
Diagnostic Aids
and Go to Step
3
3 1. Using the Tech2, ignition “On” and engine “Off”.
2. Select “Clear DTC Information” with the Tech2 and
clear the DTC information.
3. Operate the vehicle and monitor the “F5: Failed
This Ignition” in “F2: DTC Information”.
Was the DTC P0113 stored in this ignition cycle?—Go to Step 4Refer to
Diagnostic Aids
and Go to Step
4
4 Check for poor/faulty connection at the IAT sensor or
ECM connector. If a poor/faulty connection is found,
repair as necessary.
Was the problem found?
—Verify repair Go to Step 5
5 Visually check the IAT sensor.
Was the problem found? —Go to Step 12Go to Step 6
C56(J2) C121
1
22
6E–136 ENGINE DRIVEABILITY AND EMISSIONS
DIAGNOSTIC TROUBLE CODE (DTC) P0117 ENGINE COOLANT
TEMPERATURE SENSOR LOW INPUT
Condition for setting the DTC and action taken when the DTC sets
Circuit Description
The engine coolant temperature (ECT) sensor is a
thermistor mounted in the engine coolant stream. The
engine control module (ECM) applies a voltage (about 5
volts) through a pull-up resistor to the ECT signal circuit.
When the engine coolant is cold, the sensor (thermistor)
resistance is high, therefore the ECM will measure a
high signal voltage. As the engine coolant warms, the
sensor resistance becomes lower, and the ECT signal
voltage measured at the ECM drops. Diagnostic Trouble
code P0117 set when the ECM detects an ex cessively
low signal voltage on the engine coolant temperature
sensor signal circuit.
Diagnostic Aids
Check for the following conditions:
Poor connection at ECM - Inspect harness
connectors for backed-out terminals, improper
mating, broken locks, improperly formed or damaged
terminals, and poor terminal-to-wire connection.
Damaged harness - Inspect the wiring harness for
damage, short to ground, short to battery positive,
and open circuit. If the harness appears to be OK,
observe the ECT display on the Tech 2 while moving
connectors and wiring harnesses related to the ECT
sensor. A change in the ECT display will indicate the
location of the fault.
Code Type DTC Name DTC Setting Condition Fail-Safe (Back Up)
P0117 A Engine Coolant Temperature Sensor
Lo w Input1. Engine run time is longer than 120 sec-
onds.
2. ECT sensor output is more than 149 deg.
C. The ECM uses default engine coolant
temperature value based on intake air
temperature and engine run time.
ENGINE DRIVEABILITY AND EMISSIONS 6E–139
DIAGNOSTIC TROUBLE CODE (DTC) P0118 ENGINE COOLANT
TEMPERATURE SENSOR HIGH INPUT
Condition for setting the DTC and action taken when the DTC sets
Circuit Description
The engine coolant temperature (ECT) sensor is a
thermistor mounted in the engine coolant stream. The
engine control module (ECM) applies a voltage (about 5
volts) through a pull-up resistor to the ECT signal circuit.
When the engine coolant is cold, the sensor (thermistor)
resistance is high, therefore the ECM will measure a
high signal voltage. As the engine coolant warms, the
sensor resistance becomes less, and the ECT signal
voltage measured at the ECM drops. Diagnostic Trouble
code P0118 set when the ECM detects an ex cessively
high signal voltage on the engine coolant temperature
sensor signal circuit.
Diagnostic Aids
Check for the following conditions:
Poor connection at ECM - Inspect harness
connectors for backed-out terminals, improper
mating, broken locks, improperly formed or damaged
terminals, and poor terminal-to-wire connection.
Damaged harness - Inspect the wiring harness for
damage, short to ground, short to battery positive,
and open circuit. If the harness appears to be OK,
observe the ECT display on the Tech 2 while moving
connectors and wiring harnesses related to the ECT
sensor. A change in the ECT display will indicate the
location of the fault.
Code Type DTC Name DTC Setting Condition Fail-Safe (Back Up)
P0118 A Engine Coolant Temperature Sensor
High Input1. Engine run time is longer than 120 sec-
onds.
2. ECT sensor output is below -38 deg.C. The ECM uses default engine coolant
temperature value based on intake air
temperature and engine run time.
ENGINE DRIVEABILITY AND EMISSIONS 6E–143
DIAGNOSTIC TROUBLE CODE (DTC) P0122 THROTTLE POSITION SENSOR
LOW INPUT
Condition for setting the DTC and action taken when the DTC sets
Circuit Description
The throttle position sensor circuit provides a signal
voltage that changes relative to throttle blade angle. The
signal voltage will vary from below 1 volt at closed
throttle to about 4 volts at wide open throttle (WOT).
The TPS signal is used by the engine control module
(ECM) for fuel control and most of the ECM-controlled
outputs. If the ECM detect a continuous short to ground
in the TPS or circuit, then a code P0122 will set.
Diagnostic Aids
Poor connection at ECM - Inspect harness
connectors for backed-out terminals, improper
mating, broken locks, improperly formed or damaged
terminals, and poor terminal-to-wire connection.
Damaged harness - Inspect the wiring harness for
damage, short to ground, short to battery positive,
and open circuit. If the harness appears to be OK,
observe the throttle position display on the Tech 2
while moving connectors and wiring harnesses
related to the TPS. A change in the display will
indicate the location of the fault.
Code Type DTC Name DTC Setting Condition Fail-Safe (Back Up)
P0122 A Throttle Position Sensor Low Input TPS output voltage is below 0.14V. The ECM uses 0% condition as substitute.