3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-331
ENGINE CRANKS BUT WILL NOT RUN
DEFINITIONS: Engine cranks, but will not run. (The
engine never start.)
NOTE: The replacement ECM must be programmed.
Refer to section of the Service Programming
System (SPS) in this manual. Following ECM
programming, the immobilizer system (if equipped)
must be linked to the ECM. Refer to section 11
"Immobilizer System-ECM replacement" for the
ECM/Immobilizer linking procedure.
Should Tech2 display "SPS Procedure was not
successful", engine will not start, but no DTCs are
present, low battery voltage or poor electrical
connections should be the primary
suspects.Perform the SPS procedure again after
rectifying the fault/s.
NOTE: The vehicle with immobilizer system, this
system may be activated. Check the immobilizer
system diagnosis.
Step Action Value (s) Yes No
1
Was the "On-Board Diagnostic (OBD) System Check"
performed?
- Go to Step 2 Go to On Board
Diagnostic (OBD)
System Check
2
1. Perform a bulletin search.
2. If a bulletin that addresses the symptom is found,
correct the condition as instructed in the bulletin.
Was a bulletin found that addresses the symptom?
- Verify repair Go to Step 3
3
Was a visually/physical check performed?
- Go to Step 4 Go to Visual /
physical Check
4
Check the "Meter" fuse (15A), "Engine" fuse (15A),
"IGN Coil" fuse (15A) and "Fuel Pump" fuse (20A). If
the fuse is burnt out, repair as necessary.
Was the problem found?
- Verify repair Go to Step 5
5
Check the ECM grounds to verify that they are clean
and tight. Refer to the ECM wiring diagrams.
Was a problem found?
- Verify repair Go to Step 6
6
Check the fuel quality.
Is the customer using proper fuel?
- Go to Step 7
Replace fuel
7
Visually/physically inspect for the following conditions:
Restrict air intake system. Check for a restricted air
filter element, or foreign objects blocking the air
intake system.
Check for objects blocking the IAC passage or
throttle bore, excessive deposits in the throttle bore
and on the throttle plate.
Check for a condition that causes a large vacuum
leak, such as an incorrectly installed or faulty
crankcase ventilation hose/brake booster hose.
Was a problem found?
- Verify repair Go to Step 8
6E-368 3.5L ENGINE DRIVEABILITY AND EMISSIONS
ON-VEHICLE SERVICE PROCEDURE
ENGINE CONTROL MODULE (ECM)
NOTE:
To prevent possible electrostatic discharge
damage, follow these guidelines:
Do not touch the control module connector pins
or soldered components on the control module
circuit board.
Do not open the replacement part package until
the par is ready to be installed.
Before removing the part from the package,
ground the package to a known good ground on
the vehicle.
If the part has been handled while sliding across
the seat, or while sitting down from a standing
position, or while walking a distance, touch a
known good ground before installing the part.
NOTE:
To prevent internal ECM damage, the ignition must
be in the "OFF" position in order to disconnect o
r
reconnect power to the ECM (for example: battery
cable, ECM pigtail, ECM fuse, jumper cables, etc.).
NOTE:
When replacing the production ECM with a service
ECM, it is important to transfer the broadcast code
and production ECM number to the service ECM
label. This will allow positive identification of ECM
parts throughout the service life of the vehicle.
Location
On the common chamber.
Removal Procedure
1. Disconnect the negative battery cable.
2. Disconnect the two connectors from the ECM.
3. Remove four bolts.
4. Remove the ECM from common chamber.
Installation Procedure
1. Put on the ECM on the common chamber.
2. Tighten the ECM by four bolts.
3. Connect the two connectors to the ECM.
4. Connect the negative battery cable.
NOTE:
The replacement ECM must be programmed.
Service Programming System (SPS) and
Immobilizer programming (if equipped) is
/are
necessary. In case "SPS procedure does not
succeed" or "engine does not run but No DTC afte
r
SPS", low vehicle battery voltage or disconnected
electrical connector (e.g. poor connection of data
link connector) are supposed. Perform the SPS
procedure once again by correct conditions. The
programming ECM will be recovered normally.
ENGINE DIAGNOSIS (C24SE) 6-3
3.Trouble in Fuel System
Condition Possible cause Correction
Starting motor turns over and
spark occurs but engine does not
start. Fuel tank empty Fill
Water in fuel system Clean
Fuel filter clogged Replace filter
Fuel pipe clogged Clean or replace
Fuel pump defective Replace
Fuel pump circuit open Correct or replace
Evaporative Emission Control
system circuit clogged Correct or replace
Multiport Fuel Injection System
faulty Refer to "Electronic Fuel Injection"
section
4.Engine Lacks Compression
Condition Possible cause Correction
Engine lacks compression Spark plug loosely fitted or spark
plug gasket defective Tighten to specified torque or
replace gasket
Spark plug wire incorrect Connect properly or replace
Valve timing incorrect Adjust
Cylinder head gasket defective Replace gasket
Valve incorrectly seated Lap valve
Valve stem seized Replace valve and valve guide
Valve spring weakened Replace
Cylinder or piston rings worn Overhaul engine
Piston ring seized Overhaul engine.
Engine Compression Test Procedure
1. Start and run the engine until the engine
reaches normal operating temperature.
2. Turn the engine off.
3. Remove all the spark plugs.
4. Remove ignition coil fuse (15A) and disable the
ignition system.
5. Remove the fuel pump relay from the relay and
fuse box. 6. Engage the starter and check that the cranking
speed is approximately 300 rpm.
7. Install cylinder compression gauge into spark
plug hole.
8. With the throttle valve opened fully, keep the
starter engaged until the compression gauge
needle reaches the maximum level. Note the
reading.
9. Repeat the test with each cylinder.
The pressure difference between the individual
cylinders should not exceed 100kPa (14.5 psi).
6D1-2 ENGINE ELECTRICAL
Battery
General Description
There are six battery fluid caps on top of the battery.
These are covered by a paper label.
The battery is completely sealed except for the six small vent
holes on the side. These vent holes permit the escape of small
amounts of gas generated by the battery.
This type of battery has the following advantages over
conventional batteries:
1. There is no need to add water during the entire service life
of the battery.
2. The battery protects itself against overcharging.
The battery will refuse to accept an extensive charge.
(A conventional battery will accept an excessive charge,
resulting in gassing and loss of battery fluid.)
3. The battery is much less vulnerable to self discharge than a
conventional type battery.
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.
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
ENGINE DRIVEABILITY AND EMISSIONS 6E–29
No. Connector face No. Connector face
E-84
Knock sensorP-1
Silver Battery (+)
E-85
MAP sensorP-2
Silver Relay & Fuse box
F-2
White Fuel pump & sensorP-5
Silver Battery (-)
H-4
White Engine room ~ MissionP-6
Silver Body earth (Ground)
H-6
White Engine room ~ INSTP-10
Silver Engine ground
H-7
White Engine room ~ INSTX-2
Black Relay; Fuel pump
H-9
Blue Engine room ~ ChassisX-11
Black Relay; Heater
H-18
White Engine room ~ INSTX-14
Black Relay; A/C Compressor
H-31
Engine room ~ Mission
H-34
Engine ~ Engine room
6E–30 ENGINE DRIVEABILITY AND EMISSIONS
RELAY AND FUSE
RELAY A ND FUSE BOX LOCATION (LHD & RHD)
LHD
RHD
ENGINE DRIVEABILITY AND EMISSIONS 6E–31
RELAY A ND FUSE BOX LOCATION (LHD & RHD)
RELAY & FUSE BOX
RELAY
No. Relay Name
X-1 RELAY; TAIL LIGHT
X-2 RELAY; FUEL PUMP
X-3 RELAY; HORN
X-4 RELAY; DIMMER
X-5 RELAY; FRT FOG
LIGHT (LHD only)
X-6 RELAY; STARTER
X-7 RELAY; COND, FAN
X-8—
X-9—
X-10—
X-11 RELAY; HEATER
X-12 RELAY; HEAD LIGHT
X-13—
X-14 RELAY; A/C COMP
X-15 RELAY; THERMO
FUSE
NO. Fuse Name
EB-1 15A ECM
EB-2—
EB-3 15A FRT FOG
EB-4 15A ACG (S)
EB-5 10A ILLUMI
EB-6 10A TAIL
EB-7 10A H/LIGHT-RH
10A H/LIGHT-RH-LOW
EB-8 10A H/LIGHT-LH
10A H/LIGHT-LH-LOW
(LHD only)
EB-9 20A FUEL PUMP
EB-10 10A O
2 SENSOR
EB-11 10A H/LIGHT-RH-
HIGH (LHD only)
EB-12 10A H/LIGHT-LH-
HIGH (LHD only)
EB-13 10A A/C
EB-14—
EB-15 10A HORN
EB-16 10A HAZARD
SLOW BLOW FUSE
NO. Slow Blow Fuse Name FUSE NO. Slow Blow Fuse Name
SBF-1 100A MAIN SBF-6—
SBF-2—SBF-7—
SBF-3—SBF-8 30A BLOWER
SBF-4 20A COND, FAN SBF-9 50A IG 2
SBF-5 40A IG 1