sensor ISUZU KB P190 2007 Workshop Repair Manual

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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Engine Control System (4JH1) 6E-273
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.
• Inspect for a worn or damaged turbocharger turbine wheel, shaft or compressor
wheel. Refer to turbocharger inspection in the Engine Mechanical section.
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 Check 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).
• Inspect for incorrect basic engine parts such as camshaft, cylinder head, pistons,
etc.
• Inspect for any excessive oil entering combustion chamber.
• Improper mechanical timing
• Improper valve gap
• Broken or weak valve springs
• W orn camshaft lobes
Additional Checks •
Inspect the EGR system operating correctly.
• Inspect the excessive blow-by gasses.
• Inspect the scan tool Data List in this section.


Excessive Smoke (White Smoke)
Checks Action
DIFINITION:W hite 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.
• Inspect the fuel quality (cetane index).
• Inspect the Service Bulletins for ECM software updates.
Sensor Check 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.
• Inspect the crankshaft position (CKP) sensor is tight and the flywheel circumference
is not damaged.
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-274 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 leak in the intake manifold.
• Inspect for a restriction or damage at MAF sensor.
• Inspect for a worn or damaged turbocharger turbine wheel, shaft or compressor
wheel. Refer to turbocharger inspection in the Engine Mechanical section.
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).
• Inspect for incorrect basic engine parts such as camshaft, cylinder head, pistons,
etc.
• Improper mechanical timing
• Improper valve gap
• Broken or weak valve springs
• W orn camshaft lobes
• Inspect for any excessive fuel entering combustion chamber.
• Inspect for coolant entering the combustion chamber.
Electrical System Checks Inspect the engine electrical for the following conditions. Refer to the Engine Electrical
section.
• Inspect the glow plug control (preheating) system operation.



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Engine Control System (4JH1) 6E-279
Important:
Refer to Service Bulletins before service programming is
performed if the bulletins are listed along with the
calibration files.
Important:
Select Cancel if you receive a message stating that the
calibration selected is already the current calibration in
the scan tool and reprogramming with the same
download is not allowed.
14. Select Reprog.
15. The Transfer Data screen will appear until the progress bar reaches 100%.
Important:
The vehicle fitted with automatic transmission, Check
Trans lamp may blink while programming the ECM since
communication between the ECM and TCM is
interrupted. Clear DTC in any module afte
r
programming. 16. Select Close on the Programming Complete
screen.
17. Turn OFF the scan tool.
18. Disconnect the scan tool from the vehicle.

Accelerator Pedal Position (APP) Sensor
Replacement
Removal Procedure 1. Disconnect the negative battery cable.
2. Disconnect the APP sensor connector.
3. Loosen two screws and remove APP sensor from the throttle body.








Installation Procedure 1. Temporary tighten the APP sensor by two screws. 2. Connect a APP sensor connectors to the
APP
sensor.
3. Connect the Tech2 to the vehicle.
4. Connect the negative battery cable.
5. Select "Data Display" with the Tech2.
6. Check the APP sensor data and adjust the
APP
sensor.
7. Tighten two screws.

Crankshaft Position (CKP) Sensor
Replacement
Removal Procedure
1. Disconnect the negative battery cable.
2. Disconnect connector from the CKP sensor.
3. Loosen a bolt and remove the CKP sensor from the clutch housing.







Installation Procedure
1. Install the CKP sensor to the clutch housing.
2. Tighten CKP sensor by a bolt with specified tightening torque.
Tightening Torque
• Bolts: 8.0 - 12.0 N.m (0.8 - 1.2 kgf.m)
3. Connect a CKP sensor connector to the CKP sensor.
4. Connect the negative battery cable.


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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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Engine Control System (4JH1) 6E-281






Installation Procedure
1. Install the MAF & IAT sensor assembly into intake air duct.
2. Tighten the clips.
3. Connect a MAF & IAT sensor connector to the MAF & IAT sensor assembly.
4. Connect the negative battery cable.

Turbocharger Solenoid Valve Replacement
[High Altitude Spec]
Removal Procedure
1. Disconnect the negative battery cable.
2. Disconnect a harness connector from the turbocharger solenoid valve.
3. Disconnect two hoses from the turbocharge
r
solenoid valve.
4. Loosen a nut and remove the turbocharger solenoid valve from the bracket.




RTW 66ESH004001
Legend
1. Vaccum Pressure Sensor
2. To Turbocharger
3. EGR Solenoid Valve
4. To Vacuum Regulating Valve
5. Turbocharger Solenoid Valve


Installation Procedure
1. Set the turbocharger solenoid valve on the bracke
t
and tighten a nut.
2. Connect a harness connector to the turbocharge
r
solenoid valve.
3. Connect two hoses to the turbocharger solenoid valve.
4. Connect the negative battery cable.

Vacuum Pressure Sensor Replacement
[High Altitude Spec]
Removal Procedure
1. Disconnect the negative battery cable.
2. Disconnect a harness connector from the vacuum pressure sensor.
3. Loosen a bolt and remove the vacuum pressure sensor from the bracket.





RTW 66ESH004001
Legend
1. Vaccum Pressure Sensor
2. To Turbocharger
3. EGR Solenoid Valve
4. To Vacuum Regulating Valve
5. Turbocharger Solenoid Valve



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6E-282 Engine Control System (4JH1)
Installation Procedure 1. Set the vacuum pressure sensor on the bracket and tighten a bolt.
2. Connect a harness connector to the vacuum pressure sensor.
3. Connect the negative battery cable.

Vehicle Speed Sensor (VSS) Replacement
Removal Procedure
M/T & A/T (4W D) 1. Disconnect the negative battery cable.
2. Disconnect a harness connector from the vehicle speed sensor (VSS).
3. Remove the VSS from the transmission.









A/T (2W D)
1. Disconnect the negative battery cable.
2. Disconnect a harness connector from the vehicle speed sensor (VSS).
3. Loosen a bolt and remove the VSS from the transmission.







Installation Procedure
M/T & A/T (4W D) 1. Install the VSS at the transmission.
2. Connect a harness connector to the VSS.
3. Connect the negative battery cable.

M/T & A/T (4W D) 1. Set the VSS at the transmission and tighten a bolt.
2. Connect a harness connector to the VSS.
3. Connect the negative battery cable.

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Engine Control System (4JH1) 6E-283
Description And Operation
Engine Control Module (ECM) Description



RTW 66ESH001201
The engine control module (ECM) is designed to
withstand normal current draws associated with vehicle
operation. Avoid overloading any circuit. W hen testing
for opens and shorts, do not ground or apply voltage to
any of the ECM circuits unless instructed to do so. In
some cases, these circuits should only be tested using
a digital multi meter (DMM). The ECM should remain
connected to the ECM harness.
The ECM is located on the floor panel. The ECM mainl
y
controls the following.
• The fuel system control
• The exhaust gas recirculation (EGR) system
control
• The preheating (glow) system control
• The A/C compressor control
• On-board diagnostics for engine control
The ECM constantly observes the information from
various sensor s. The ECM controls the systems that
affect vehicle performance. The ECM performs the
diagnostic function of the system. The ECM can
recognize operational problems, alert the driver through
the malfunction indicator lamp (MIL), and store
diagnostic trouble codes (DTCs). DTCs identify the
system faults to aid the technician in making repairs.





ECM Voltage Description
The ECM supplies a buffered voltage to various
switches and sensor s. The ECM can do this because
resistance in the ECM is so high in value that a test
lamp may not illuminate when connected to the circuit.
An ordinary shop voltmeter may not give an accurate
reading because the voltmeter input impedance is too
low. Use a 10-megaohm input impedance DMM, to
ensure accurate voltage readings. The input and/o
r
output devices in the ECM include analog-to-digital
converters, signal buffers, counters, and special drivers.
The ECM controls most components with electronic
switches which complete a ground circuit when turned
ON.
Aftermarket Electrical and Vacuum Equipment
Aftermarket or add-on electrical and vacuum equipment
is defined as any equipment which connects to the
vehicle's electrical or vacuum systems that is installed
on a vehicle after the vehicle leaves the factory. No
allowances have been made in the vehicle design fo
r
this type of equipment. No add-on vacuum equipment
should be added to this vehicle. Add-on electrical
equipment must only be connected to the vehicle's
electrical system at the battery power and ground. Add-
on electrical equipment, even when installed to these
guidelines, may still cause the powertrain system to
malfunction. This may also include equipment not
connected to the vehicle electrical system such as
portable telephones and audios. Therefore, the first
step in diagnosing any powertrain fault is to eliminate all
aftermarket electrical equipment from the vehicle. Afte
r
this is done, if the fault still exists, the fault may be
diagnosed in the normal manner.
Electrostatic Discharge Damage
Electronic components used in the ECM are often
designed to carry very low voltage. Electronic
components are susceptible to damage caused b
y
electrostatic discharge. By comparison, as much as
4,000 volts may be needed for a person to feel even the
zap of a static discharge. There are several ways for a
person to become statically charged. The most
common methods of charging are by friction and
induction. •
An example of charging by friction is a person
sliding across a vehicle seat.


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6E-284 Engine Control System (4JH1)
Important:
To prevent possible electrostatic discharge damage,
follow these guidelines: • Do not touch the ECM connector pins or soldered
components on the ECM circuit board.
• Do not open the replacement part package until
the part 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, while sitting down from a standing
position, or while walking a distance, touch a
known good ground before installing the part.
• Charge by induction occurs when a person with
well insulated shoes stands near a highly charged
object and momentarily touches ground. Charges
of the same polarity are drained off leaving the
person highly charged with opposite polarity.
Malfunction Indicator Lamp (MIL) Operation
The malfunction indicator lamp (MIL) is located in the
instrument panel cluster (IPC). The MIL will display the
following symbols when commanded ON:



RTW 76ESH004001
The MIL indicates that an emission or performance
related fault has occurred and vehicle service is
required. The following is a list of the modes o
f
operation for the MIL: • The MIL illuminates for approximately 2 seconds
when the ignition switch is turned ON, with the
engine OFF. This is a bulb test to ensure the MIL
is able to illuminate.

•
The MIL remains illuminated after the engine is
started if the ECM detects a fault. A DTC is stored
any time the ECM illuminates the MIL due to an
emission or performance related fault.

Engine Control Component Description
Accelerator Pedal Position (APP) Sensor & Idle
Switch






RTW 66ESH001301
The accelerator pedal position (APP) sensor is mounted
on the throttle assembly. The engine control module
(ECM) uses the APP sensor s to determine the amount
of acceleration or deceleration desired by the person
driving the vehicle via the fuel injection control.
The idle switch is also mounted on the intake throttle
assembly. The idle switch is part of the APP senso
r
assembly. The idle switch is a normally closed type
switch. W hen the accelerator pedal is released, the idle
switch signal to the ECM is low voltage.








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Engine Control System (4JH1) 6E-285
Crankshaft Position (CKP) Sensor










RTW 06ESH000101




RTW 66ESH001401
Legend
1. Crankshaft Position (CKP) Sensor
2. Flywheel
3. Slit

The crankshaft position (CKP) sensor is located on top
of the flywheel housing. There are 4 slits spaced 90 °
on the flywheel circumference. The CKP sensor is a
magnetic coil type sensor , which generates an AC
signal voltage based on the crankshaft rotational speed.
The ECM monitors both the CKP sensor and injection
pump camshaft position (CMP) sensor signals to
ensure they correlate with each other.

The following waveform aids to diagnose when there is
an oscilloscope or equivalent.

Engine Coolant Temperature (ECT) Sensor
- Amplitudes of CKP sensor signal (CH1) increase as engine speed increases.
- Each waveform cycle shorten as the engine speed increases.
Terminal: 90 (CH1), 91 (CH2) (+) / GND (-)
Scale: 10V/div 2ms/div
Condition: Approximately 1000RPM

CH1
0V
CH2 0V


RTW 66ESH001501
Legend
1. Engine Coolant Temperature (ECT) Sensor

The engine coolant temperature (ECT) sensor is
installed to the thermostat housing. The ECT sensor is
a variable resistor. The ECT sensor measures the
temperature of the engine coolant. The engine control
module (ECM) supplies 5 volts to the ECT signal circuit
and a ground for the ECT low reference circuit. W hen
the ECT sensor is cold, the sensor resistance is high.
W hen the engine coolant temperature increases, the
sensor resistance decreases. W ith high senso
r
resistance, the ECM detects a high voltage on the ECT
signal circuit. W ith lower sensor resistance, the ECM
detects a lower voltage on the ECT signal circuit.

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