
6E-272 Engine Control System (4JH1)
Checks Action
Air Intake System Checks Inspect the air intake system for the following conditions.
• Inspect the air cleaner and air intake ducts for a restriction, holes, or leaks.
• Inspect for a restriction or leak in the intercooler.
• Inspect for a restriction in the turbocharger inlet duct.
• Inspect for a restriction or deposit in the intake throttle bore.
• Inspect for a restriction or leak in the intake manifold.
• Inspect for a restriction or damage at MAF sensor.
Exhaust System Checks Inspect the exhaust system for a possible restriction. Refer to the Exhaust System
section.
• Inspect for a restriction in the catalytic converter or exhaust pipes.
Engine Mechanical Checks Inspect the engine mechanical for the following conditions. Refer to the Engine
Mechanical section.
• Inspect for poor cylinder compression. Proper compression is more than 2100 kPa
(309 psi).
Excessive Smoke (Black Smoke)
Checks Action
DEFINITION:Black smoke under load, idle or start up hot or cold.
Preliminary Check •
Ensure the vehicle has an actual problem.
• Inspect the engine control module (ECM) and fuel injection pump control unit (PCU)
grounds for being clean, tight, and in their proper locations.
• Remove the air cleaner and check for dirt, or for air ducts being plugged or
restricted. Replace as necessary.
• Inspect the fuel quality (cetane index).
• Inspect the engine oil level and quality.
• Inspect the Service Bulletins for ECM software updates.
Sensor Checks Inspect the engine control sensors for the following conditions. Refer to the scan tool
Data List in this section.
• Use the scan tool to compare the Engine Coolant Temperature (ECT) with the Intake
Air Temperature (IAT) and Fuel Temperature (FT) on a cold engine condition. If the
difference among temperature reading is more than 5°C (9°F) on a cold engine,
check for high resistance on the low reference circuit and signal circuit or for a
skewed sensor.
Notice: The mass air flow (MAF) sensor is heated and as a result the IAT sensor may
indicate a higher than normal intake air temperature if the ignition switch is being ON.
FT sensor is internal to the PCU and it is part of the fuel injection pump assembly.
• Use the scan tool to compare the MAF Sensor parameter with the Desired MAF
parameter. Start the engine and warm up (allow engine coolant temperature to reach
at least 60°C [140°F]). The MAF Sensor parameter must follow the Desired MAF
parameter within 100 mg/strk. If not, inspect the air intake system, EGR system
components and contaminated, skewed or slow MAF sensor.
• Use the scan tool to observe the Accelerator Pedal Position Accelerator Pedal
Position. Accelerator Pedal Position indicating angle parameter should change
linearly from 0% to 100% according to the accelerator pedal operation.
Fuel System Checks Inspect the fuel system for the following conditions. Refer to the Fuel System section.
• Inspect the fuel injection nozzle(s) for proper splay condition or operating pressure.
Notice: Only first stage of operating pressure can be checked.
• Inspect the timing device operating correctly. Observe the Actual Injection Timing
parameter with the scan tool while running the engine. The Actual Injection Timing
parameter must follow the Desired Injection Timing within 2°CA on each engine
speed. Engine idle > around 2000 RPM> around 3000 RPM. If not, inspect the fuel
system restriction, air in the fuel or fuel injection pump operation.
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ISUZU KB P190 2007

6E-280 Engine Control System (4JH1)
EGR Solenid Valve Replacement
Removal Procedure 1. Disconenct the negative battery cable.
2. Disconnect a EGR solenoid valve harness connector.
3. Disconnect two hoses from the EGR solenoid valve.
4. Loosen two bolts and remove the EGR solenoid valve from the bracket.
Installation Procedure
1. Tighten the purge solenoid by tow bolts.
2. Connect a connector to the EGR solenoid valve.
3. Connect two hoses to the EGR solenoid valve.
4. Connect the negative battery cable.
Engine Coolant Temperature (ECT) Sensor
Replacement
1. Removal Procedure
2. Disconnect the negative battery cable.
3. Drain enough engine coolant so that the coolant level will be below the ECT sensor.
4. Disconnect connector from the ECT sensor.
5. Loosen and remove the ECT sensor from the thermostat housing.
Notice: Cool down the engine before above procedures
are carried out.
Installation Procedure
1.
Apply sealer to threads of screw at the ECT
sensor.
2. Tighten the ECT sensor with specified tightening torque.
Tightening Torque • Bolt: 13 N.m (1.3 kgf.m)
3. Connect a ECT sensor connector to the ECT sensor.
4. Fill the engine coolant.
5. Connect the negative battery cable.
Notice: Verify no engine coolant leaking from the
sensor threads after replacement.
Mass Air Flow (MAF) / Intake Air
Temperature (IAT) Sensor Replacement
Removal Procedure
1. Disconnect the negative battery cable.
2. Disconnect a MAF & IAT sensor connector from the MAF & IAT sensor assembly.
3. Loosen the clips and remove the MAF & IAT sensor assembly from the intake duct housing.
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6B-6 ENGINE COOLING (4JK1/4JJ1)
Diagnosis
Engine Cooling Trouble
Condition Possible Cause Correction
Low Engine Coolant level Replenish
Thermo meter unit faulty Replace
Faulty thermostat Replace
Faulty Engine Coolant temperature
sensor Repair or replace
Clogged radiator
Clean or replace
Faulty radiator cap Replace
Low engine oil level or use of
improper engine oil Replenish or change oil
Clogged exhaust system
Clean exhaust system or replace
faulty parts
Faulty Throttle Position sensor Replace throttle valve assembly
Open or shorted Throttle Position
sensor circuit Repair or replace
Engine overheating
Damaged cylinder head gasket Replace
Engine overcooling Faulty thermostat Replace
Faulty thermostat Replace Engine slow to warm–up
Thermo unit faulty Replace
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ENGINE COOLING (4JK1/4JJ1) 6B-7
Draining and Refilling Cooling System
Before draining the cooling system, inspect the system
and perform any necessary service to ensure that it is
clean, does not leak and is in proper working order.
The engine coolant (EC) level should be between the
“MIN" and “MAX" lines of the reserve tank when the
engine is cold. If low, check for leakage and add EC up
to the “MAX" line.
There should not be any excessive deposit of rust o
r
scales around the radiator cap or radiator filler hole, and
the EC should also be free from oil.
Replace the EC if excessively dirty.
1. Remove the radiator skid plate.
2. Completely drain the cooling system by opening the drain plug at the bottom of the radiator.
RTW 56BSH000301
3. Remove the radiator cap.
WARNING:
To avoid the danger of being burned, do not
remove the cap while the engine and radiator are
still hot. Scalding fluid and steam can be blown out
under pressure.
4. Disconnect all hoses from the EC reserve tank.
Scrub and clean the inside of the reserve tank with soap and water. Flush it well with clean water,
then drain it. Install the reserve tank and hoses.
5. Refill the cooling system with the EC using a
solution that is at least 50 percent antifreeze.
Procedure for filling with coolant (in case of full change).
• Make sure that the engine is cool.
• Open radiator cap and pour coolant up to fille
r
neck.
• Pour coolant into reservoir tank up to “MAX" line.
• Tighten radiator cap and start the engine. Afte
r
idling for 2 to 3 minutes, stop the engine and
reopen the radiator cap. If the water level is lower,
replenish.
WARNING:
When the coolant is heated to a high temperature,
be sure not to loosen or remove the radiator cap.
Otherwise you might get scalded by hot vapor o
r
boiling water. To open the radiator cap, put a piece
of thick cloth on the cap and loosen the cap slowly
to reduce the pressure when the coolant has
become cooler.
• After tightening the radiator cap, warm up the
engine at about 2000 rpm. Set heater adjustment
to the highest temperature position, and let the
coolant circulate also into heater water system.
• Check to see the thermostat has opened through
the needle position of the water thermometer,
conduct a 5–minute idling again and stop the
engine.
• W hen the engine has been cooled, check fille
r
neck for water level and replenish if required.
Should extreme shortage of coolant be found,
check the cooling system and reservoir tank hose
for leakage.
• Pour coolant into the reservoir tank up to “MAX"
line.
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ENGINE CONTROL SYSTEM (4JK1/4JJ1) 6E-3
Specifications
Temperature vs Resistance
Engine Coolant Temperature vs. Resistance
Intake Air Temperature vs. Resistance
Fuel Temperature vs. Resistance
Altitude vs Barometric Pressure
° C °FOhms
Temperature vs. Resistance Value (Approximately)
110 230 160
100 212 200 90 194 260
80 176 350
70 158 470
60 140 640
50 122 880
40 104 1250
30 86 1800
20 68 2650
10 50 4000 0 32 6180
-10 14 9810
-20 -4 16000
-30 -22 27000
° C °FOhms
Temperature vs. Resistance Value (Approximately)
90 194 240
80 176 320
70 158 430
60 140 590
50 122 810
40 104 1150
30 86 1650
20 68 2430
10 50 3660
0325650
-10 14 8970
-20 -4 14700
° C °FOhms
Temperature vs. Resistance Value (Approximately) 110 230 140
100 212 180
90 194 24080 176 310
70 158 420
60 140 580
50 122 810
40 104 1150
30 861660
20 682450
10 503700
03 2574 0
-10 149160
-20 -415000
-30 -2225400
Altitude Measured in Meters (m) Altitude Measured
in Feet (ft) Barometric
Pressure
Measured in
Kilopascals (kPa)
Determine your altitude by contacting a local weather station or by using another reference source.
4267 14000 56 - 64
3962 13000 58 - 66
3658 12000 61 - 69
3353 11000 64 - 72
3048 10000 66 - 74
2743 900069 - 77
2438 800071 - 79
2134 700074 - 82
1829 600077 - 85
1524 500080 - 88
1219 400083 - 91
914 300087 - 98
610 200090 - 98
305 100094 - 102
0 0 Sea Level 96 - 104
-305 -1000101 - 105
°
C °FO hm s
Temperature vs. Resistance Value (Approximately)
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ENGINE CONTROL SYSTEM (4JK1/4JJ1) 6E-47
Scan Tool Data List
The Engine Scan Tool Data List contains all engine
related parameters that are available on the scan tool.
A given parameter may appear in any one of the data
lists, and in some cases may appear more than once,
or in more than one data list in order to group certain
related parameters together. Use the Engine Scan Tool
Data List only after the following is determined:
• The Engine Controls - Diagnostic System Check is completed. • On-board diagnostics are functioning properly.
Scan tool values from a properly running engine may
be used for comparison with the engine you are
diagnosing. The Engine Scan Tool Data List represents
values that would be seen on a normal running engine.
Only the parameters listed below are referenced in this
service manual for use in diagnosis.
Scan Tool Parameter Units Displayed Typical Data Value at Engine Idle Typical Data Value at 2000RPM
Operating Conditions: Engine idling or 2000RPM/ Engine coolant temperature is between 75 to 85 °C (167 to 185 °F)/
Accelerator pedal is constant/ Neutral or Park/ Accessories OFF/ Vehicle located at sea level
Engine Speed RPMNearly 700 RPM Nearly 2000 RPM
Desired Engine Idle Speed RPM700 RPM 700 RPM
Calculated Engine Load %- -
Coolant Temperature °C/ °F 75 to 85 °C/ 167 to 185 °F 75 to 85 °C/ 167 to 185 °F
Engine Coolant Temperature Sensor Volts
0.4 to 0.6 volts 0.4 to 0.6 volts
Intake Air Temperature °C/ °F 20 to 40 °C/ 68 to 104 °F 20 to 40 °C/ 68 to 104 °F
Intake Air Temperature Sensor Volts 1.4 to 2.3 volts1.4 to 2.3 volts
Fuel Temperature °C/ °F 20 to 60 °C/ 68 to 140 °F 20 to 60 °C/ 68 to 140 °F
Fuel Temperature Sensor Volts0.8 to 2.3 volts 0.8 to 2.3 volts
MAF (Mass Air Flow) g/sec300 to 600 g/sec 200 to 600 g/sec
MAF Sensor (Mass Air Flow) Volts1.2 to 1.6 volts 2.0 to 2.7 volts
Barometric Pressure kPa/psi Nearly 100 kPa/ 14.5 psi at sea
levelNearly 100 kPa/ 14.5 psi at sea
level
Barometric Pressure Sensor VoltsNearly 2.3 volts at sea level Nearly 2.3 volts at sea level
Turbocharger Solenoid Command %
50 to 60 % 50 to 60 %
Desired Boost Pressure kPa/ psi Nearly 100 kPa/ 14.5 psi at sea
levelLess than 120 kPa/ 17.4 psi
Boost Pressure kPa/ psi Nearly 100 kPa/ 14.5 psi at sea
levelLess than 120 kPa/ 17.4 psi
Boost Pressure Sensor VoltsNearly 1.0 volt Less than 1.3 volts
Desired Fuel Rail Pressure MPa/ psi 30 MPa/ 4,350 psiMore than 70 MPa/ 10,200 psi
(4JJ1 Euro 4 specification)
More than 50 MPa/ 7,250 psi
(4JJ1 except Euro 4 specification)
More than 60 MPa/ 8,700 psi
(4JK1)
Fuel Rail Pressure MPa/ psi 27 to 33 MPa/ 3,900 to 4,800 psi More than 70 MPa/ 10,200 psi
(4JJ1 Euro 4 specification)
More than 50 MPa/ 7,250 psi (4JJ1 except Euro 4 specification)
More than 60 MPa/ 8,700 psi (4JK1)
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6E-50 ENGINE CONTROL SYSTEM (4JK1/4JJ1)
Scan Tool Data Definitions
This information will assist in emission or driveability
problems. The displays can be viewed while the vehicle
is being driven. Always perform the Diagnostic System
Check - Engine Controls first. The Diagnostic System
Check will confirm proper system operation.
Engine Speed
This parameter displays the rotational speed of the
crankshaft as calculated by the ECM based on inputs
from the crankshaft position (CKP) sensor or camshaft
position (CMP) sensor.
Desired Idle Speed
This parameter displays the idle speed requested by
the ECM. The ECM will change desired idle speed
based on engine coolant temperature and other inputs.
Calculate Engine Load
This parameter displays the engine load in percent
based on inputs to the ECM from various engine
sensors. The scan tool will display a lower percentage
when the engine is at idle with little or no load. The
scan tool will display a higher percentage when the
engine is running at high engine speed under a heavy
load.
Coolant Temperature
This parameter displays the temperature of the engine
coolant as calculated by the ECM using the signal from
the engine coolant temperature (ECT) sensor. The
scan tool will display a low temperature when the ECT
sensor signal voltage is high, and a high temperature
when the ECT sensor signal voltage is low.
Engine Coolant Temperature Sensor
This parameter displays the voltage signal sent to the
ECM from the engine coolant temperature (ECT)
sensor. ECT sensor is a range of value indicating a low
voltage when the temperature is high, and a high
voltage when the temperature is low.
Intake Air Temperature
This parameter displays the temperature of the intake
air as calculated by the ECM using the signal from the
intake air temperature (IAT) sensor. The scan tool will
display a low temperature when the IAT sensor signal
voltage is high, and a high temperature when the IAT
sensor signal voltage is low. Intake Air Temperature Sensor
This parameter displays the voltage signal sent to the
ECM from the intake air temperature (IAT) sensor. IAT
sensor is a range of value indicating a low voltage
when the temperature is high, and a high voltage when
the temperature is low.
Fuel Temperature
This parameter displays the temperature of the fuel as
calculated by the ECM using the signal from the fuel
temperature (FT) sensor. The scan tool will display a
low temperature when the FT sensor signal voltage is
high, and a high temperature when the FT sensor
signal voltage is low.
Fuel Temperature Sensor
This parameter displays the voltage signal sent to the
ECM from the fuel temperature (FT) sensor. FT sensor
is a range of value indicating a low voltage when the
temperature is high, and a high voltage when the
temperature is low.
MAF (Mass Air Flow)
This parameter displays the air flow into the engine as
calculated by the ECM based on the mass air flow
(MAF) sensor input. The scan tool will display a high
value at higher engine speeds, and a low value at lower
engine speed.
MAF Sensor (Mass Air Flow)
This parameter displays the voltage signal sent to the
ECM from the mass air flow (MAF) sensor. MAF sensor
is a range of value indicating a low voltage at lower
engine speed, and a high voltage at a higher engine
speeds.
Barometric Pressure
This parameter displays the barometric pressure
(BARO) as calculated by the ECM using the signal from
the BARO sensor. The scan tool will display a low
barometric pressure in high altitude area.
Barometric Pressure Sensor
This parameter displays the voltage signal sent to the
ECM from the barometric pressure (BARO) sensor.
BARO sensor is a range of value indicating a low
voltage in high altitude area, and a middle voltage in
sea level.
Immobilizer Signal Yes/ NoYes Yes
Security Wait Time Inactive/ Time
(hour: minute: second) Inactive
Inactive
Scan Tool Parameter Units Displayed Typical Data Value at Engine Idle Typical Data Value at 2000RPM
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6E-110 ENGINE CONTROL SYSTEM (4JK1/4JJ1)
DTC P0116 (Flash Code 23)
Circuit Description
The engine coolant temperature (ECT) sensor is
installed to the thermostat housing. The ECT sensor is
a variable resistor and it measures the temperature of
the engine coolant. If the ECM detects that the
difference of engine coolant temperature is smaller
than the calculated range during the predetermined
conditions, this DTC will set. This DTC will only run
once per ignition cycle within the enabling condition.
Condition for Running the DTC • DTCs P0117, P0118, P0201 - P0204, P0500, P0501 P124B, P1261, P1262 and P2146 - P2151
are not set.
• The ignition switch is ON.
• The engine coolant temperature is between -10 to 11 0 °C (14 to 230 °F).
• The vehicle run time is longer than 18 minutes.
• The engine run time is longer than 5 minutes with engine speed is more than 1200 RPM.
• The accumulation fuel injection quantity since engine start is more than a threshold.
Condition for Setting the DTC • The ECM detects that the difference of maximum and minimum engine coolant temperature is less
than 5 °C (9 °F). Action Taken When the DTC Sets
• The ECM illuminates the MIL when the diagnostic runs and fails. Refer to DTC Type Definitions for
Action Taken When the DTC Sets - Type A.
• The ECM limits fuel injection quantity.
• The ECM inhibits EGR control.
• The ECM inhibits cruise control.
Condition for Clearing the DTC • Refer to DTC Type Definitions for Condition for Clearing the MIL/ DTC - Type A.
Diagnostic Aids • After starting the engine the ECT should rise steadily to about 80 to 85 °C (176 to 185 °F) then
stabilize when the thermostat opens.
• Use the Temperature vs. Resistance table to test the ECT sensor at various temperature levels to
evaluate the possibility of a skewed sensor. A
skewed sensor could result in poor driveability
concerns.
Schematic Reference: Engine Controls Schematics
Connector End View Reference: Engine Controls
Connector End Views or ECM Connector End Views
Circuit/ System Testing DTC P0116
Step Action Value(s)Yes No
1 Did you perform the Diagnostic System Check -
Engine Controls? —
Go to Step 2 Go to Diagnostic
System Check -
Engine Controls
2 1. Test the engine cooling system for the
following condition. Refer to diagnosis of the
engine cooling system section for testing.
• Engine coolant level
• Engine coolant leakage
2. Repair or replace as necessary
Did you find and correct the condition? —
Go to Step 6 Go to Step 3
3 1. Turn OFF the ignition
2. Disconnect the engine coolant temperature (ECT) sensor harness connector.
3. Inspect for an intermittent, for poor connectors and corrosion at the harness connector of the
ECT sensor (pins 1 and 2 of E-41).
4. Disconnect the ECM harness connector.
5. Inspect for an intermittent, for poor connections and corrosion at the harness
connector of the ECM (pins 26 and 27 of E-
90).
6. Repair the connection(s) as necessary.
Did you find and correct the condition? —
Go to Step 6 Go to Step 4
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