diagram ISUZU KB P190 2007 Workshop Owner's Manual
[x] Cancel search | Manufacturer: ISUZU, Model Year: 2007, Model line: KB P190, Model: ISUZU KB P190 2007Pages: 6020, PDF Size: 70.23 MB
Page 1688 of 6020

ENGINE CONTROL SYSTEM (4JK1/4JJ1) 6E-71
DTC P0045 (Flash Code 33)
Circuit Description
The position of the turbocharger nozzle is controlled by
the ECM. The ECM utilizes a turbocharger nozzle
control solenoid valve and a boost pressure sensor to
control the turbocharger nozzles. When the engine is
not under load, the turbocharger nozzles are in an open
position, or no boost condition. When the engine is
under load, the ECM commands the control solenoid
valve to close the turbocharger nozzles, thus
increasing the boost. The ECM will vary the boost
dependant upon the load requirements of the engine.
The ECM uses a pulse width modulation (PWM) on the
control circuit to open and control the solenoid valve. If
the ECM detects an open circuit or short circuit on the
solenoid valve circuit, this DTC will set.
Condition for Running the DTC • The ignition switch is ON.
Condition for Setting the DTC
Either of following condition is met: • The ECM detects a low voltage condition on the turbocharger nozzle control solenoid circuit when
the solenoid is commanded OFF.
• The ECM detects a high voltage condition on the turbocharger nozzle control solenoid circuit when
the solenoid is commanded ON. 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 pilot injection.
• 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 • If an intermittent condition is suspected, refer to Intermittent Conditions in this section.
Test description
The number below refers to the step number on the
Circuit/ System Testing.
4. If the solenoid control circuit between the ECM and
the solenoid is normal, the test lamp changes from
Bright to Dim when commanded from Increase to
Decrease.
Schematic Reference: Vacuum Hose Routing
Diagram and Engine Controls Schematics
Connector End View Reference: Engine Controls
Connector End Views or ECM Connector End Views
Circuit/ System Testing DTC P0045
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. Install a scan tool.
2. Turn OFF the ignition for 30 seconds.
3. Start the engine.
4. Monitor the DTC Information with a scan tool.
Does the DTC fail this ignition? —
Go to Step 3 Go to Diagnostic
Aids
3 1. Turn OFF the ignition.
2. Disconnect the turbocharger nozzle control solenoid valve harness connector.
3. Connect a test lamp between the ignition voltage feed circuit (pin 2 of E-106) and a
known good ground.
4. Turn ON the ignition, with the engine OFF.
Does the test lamp illuminate? —
Go to Step 4 Go to Step 5
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ISUZU KB P190 2007
Page 1691 of 6020

6E-74 ENGINE CONTROL SYSTEM (4JK1/4JJ1)
DTC P0087 (Flash Code 225)
Description
The common rail fuel system is comprised of two fuel
pressure sections: a suction side between the fuel tank
and the fuel supply pump and a high-pressure side
between the fuel supply pump and the fuel injectors.
Fuel is drawn from the fuel tank via a feed pump and
then pumped into the fuel rail by two plungers, all of
which are internal to the fuel supply pump. This high
pressure is regulated by the ECM using the fuel rail
pressure (FRP) regulator dependant upon values from
the FRP sensor attached to the fuel rail. In case of fuel
rail overpressure, a pressure limiter valve threaded into
the fuel rail will open to release overpressure and
return fuel back to the fuel tank. If the ECM detects that
the fuel rail pressure went excessively high, then
sharply decreased, this DTC will set indicating high fuel
pressure, which activated the pressure limiter valve.
Condition for Running the DTC • DTCs P0192 and P0193 are not set.
• The battery voltage is more than 9 volts.
• The ignition switch is ON.
• The engine is running.
Condition for Setting the DTC • The ECM detects that the pressure limiter valve is activated with overpressure (more than 190 MPa
[27,600 psi]) in the fuel rail.
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 pilot injection.
• 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 • An intermittently sticking FRP regulator may have allowed the fuel pressure to become high enough
to open the pressure limiter valve.
• A skewed FRP sensor value can set this DTC. The FRP Sensor on the scan tool should read 0.9 to
1.0 volt with the key ON and engine OFF after the
engine has stopped running for a minimum of 1
minute.
Notice: • If the fuel tank is empty or near empty, air might be allowed to go into the fuel system. With air in the
fuel system, smooth flow of fuel into the supply
pump is interrupted and this DTC may set. Perform
bleeding of fuel system after refilling.
Schematic Reference: Fuel System Routing Diagram
and Engine Controls Schematics
Connector End View Reference: Engine Controls
Connector End Views or ECM Connector End Views
Circuit/ System Testing DTC P0087
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. Install a scan tool.
2. Turn OFF the ignition for 30 seconds.
3. Start the engine.
4. Monitor the DTC Information with a scan tool.
Is DTC P0088, P0089, P0091, P0092, P0192,
P0193, P0201 - P0204, P1064, P1065, P124B or
P2146 - P2151 set? —
Go to Applicable DTC Go to Step 3
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ISUZU KB P190 2007
Page 1696 of 6020

ENGINE CONTROL SYSTEM (4JK1/4JJ1) 6E-79
DTC P0088 (Flash Code 118)
Description
The common rail fuel system is comprised of two fuel
pressure sections: a suction side between the fuel tank
and the fuel supply pump and a high-pressure side
between the fuel supply pump and the fuel injectors.
Fuel is drawn from the fuel tank via a feed pump and
then pumped into the fuel rail by two plungers, all of
which are internal to the fuel supply pump. This high
pressure is regulated by the ECM using the fuel rail
pressure (FRP) regulator dependant upon values from
the FRP sensor attached to the fuel rail.
If the ECM detects that the fuel pressure went
excessively high for a certain length of time, this DTC
will set (First Stage). If the ECM detects that during the
same ignition cycle the fuel pressure rose even higher
than the amount to set DTC P0088 for a certain length
of time, the engine is stopped (Second Stage). If the
engine is stopped, the fuel pressure was too high and
the pressure limiter valve did not active or did not active
quick enough.
Condition for Running the DTC • DTCs P0192 and P0193 are not set.
• The battery voltage is more than 9 volts.
• The ignition switch is ON.
• The engine is running.
Condition for Setting the DTC
First Stage • The ECM detects that the fuel rail pressure is more than 197 MPa (28,600 psi) for longer than 5
seconds.
Second Stage
• The ECM detects that the fuel rail pressure is more than 200 MPa (29,000 psi) for longer than 5
seconds.
Action Taken When the DTC Sets
First Stage • 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 pilot injection.
• The ECM inhibits cruise control.
Second Stage • The ECM illuminates the SVS lamp when the
diagnostic runs and fails. Refer to DTC Type
Definitions for Action Taken When the DTC Sets -
Type C. (Euro 4 Specification)
• 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.
(Except Euro 4 Specification)
• The ECM limits fuel injection quantity.
• The ECM inhibits pilot injection.
• The ECM inhibits cruise control.
• The ECM stops engine running when the vehicle speed is lower than 5 km/h (3 MPH) for 5 seconds.
The engine will run after the key is cycled when the
ignition has been tuned OFF for longer than 10
seconds.
Condition for Clearing the DTC
First Stage • Refer to DTC Type Definitions for Condition for Clearing the MIL/ DTC - Type A.
Second Stage
• Refer to DTC Type Definitions for Condition for Clearing the SVS Lamp/ DTC - Type C. (Euro 4
Specification)
• Refer to DTC Type Definitions for Condition for Clearing the MIL/ DTC - Type A. (Except Euro 4
Specification)
Diagnostic Aids • An intermittently sticking Fuel Rail Pressure regulator may have allowed the fuel pressure to
become high enough to set this DTC.
• Normal Fuel Rail Pressure readings on the scan tool with the engine running in neutral at idle is
around 27 to 33 MPa (3,900 to 48,00 psi) after
warm up.
• A skewed FRP sensor value can set this DTC. The FRP Sensor on the scan tool should read 0.9 to
1.0 volt with the key ON and engine OFF after the
engine has stopped running for a minimum of 1
minute.
Schematic Reference: Fuel System Routing Diagram
and Engine Controls Schematics
Connector End View Reference: Engine Controls
Connector End Views or ECM Connector End Views
Circuit/ System Testing DTC P0088
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
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ISUZU KB P190 2007
Page 1701 of 6020

6E-84 ENGINE CONTROL SYSTEM (4JK1/4JJ1)
DTC P0089 (Flash Code 151)
Description
The common rail fuel system is comprised of two fuel
pressure sections: a suction side between the fuel tank
and the fuel supply pump and a high-pressure side
between the fuel supply pump and the fuel injectors.
Fuel is drawn from the fuel tank via a feed pump and
then pumped into the fuel rail by two plungers, all of
which are internal to the fuel supply pump. This high
pressure is regulated by the ECM using the fuel rail
pressure (FRP) regulator dependant upon values from
the FRP sensor attached to the fuel rail. If the ECM
detects that fuel pressure is a certain pressure higher
than the desired pressure, this DTC will set.
Condition for Running the DTC • DTCs P0091, P0092, P0192, P0193, P0652, P0653, P0201 - P0204, P1064, P1065, P124B and
P2146 - P2151 are not set.
• The battery voltage is more than 9 volts.
• The ignition switch is ON.
• The engine is running.
Condition for Setting the DTC • The ECM detects that the actual fuel rail pressure is more than 20 to 40 MPa (2,900 to 5,800 psi)
over the desired pressure for longer than 20
seconds. 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 pilot injection.
• 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 • An intermittently sticking FRP regulator may have allowed the fuel pressure to become high enough
to set this DTC.
• Normal Fuel Rail Pressure readings on the scan tool with the engine running in neutral at idle is
around 27 to 33 MPa (3,900 to 4,800 psi) after
warm up.
• A skewed FRP sensor value can set this DTC. The FRP Sensor on the scan tool should read 0.9 to
1.0 volt with the key ON and engine OFF after the
engine has stopped running for a minimum of 1
minute.
Schematic Reference: Fuel System Routing Diagram
and Engine Controls Schematics
Connector End View Reference: Engine Controls
Connector End Views or ECM Connector End Views
Circuit/ System Testing DTC P0089
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. Install a scan tool.
2. Turn OFF the ignition for 30 seconds.
3. Start the engine.
4. Monitor the DTC Information with a scan tool.
Is DTC P0091, P0092, P0192, P0193, P0201 -
P0204, P0219, P1064, P1065, P124B or P2146 -
P2151 set? —
Go to Applicable DTC Go to Step 3
3 1. Turn OFF the ignition.
2. Wait 1 minute for the fuel pressure to bleed down from the fuel rail.
3. Turn ON the ignition, with the engine OFF. DO NOT start the engine.
4. Observe the Fuel Rail Pressure (FRP) Sensor parameter with the scan tool.
Does the scan tool indicate within the specified
value? 0.9 to 1.0 volt
Go to Step 4 Go to Step 5
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ISUZU KB P190 2007
Page 1707 of 6020

6E-90 ENGINE CONTROL SYSTEM (4JK1/4JJ1)
DTC P0093 (Flash Code 227)
Description
The common rail fuel system is comprised of two fuel
pressure sections: a suction side between the fuel tank
and the fuel supply pump and a high-pressure side
between the fuel supply pump and the fuel injectors.
Fuel is drawn from the fuel tank via a feed pump and
then pumped into the fuel rail by two plungers, all of
which are internal to the fuel supply pump. This high
pressure is regulated by the ECM using the fuel rail
pressure (FRP) regulator dependant upon values from
the FRP sensor attached to the fuel rail. If the ECM
detects that the fuel rail pressure is certain pressure
low as compared with the engine speed, this DTC will
set.
Condition for Running the DTC • DTC P0087, P0091, P0092, P0192, P0193, P0652, P0653, P0201 - P0204, P1064, P1065,
P124B and P2146 - P2151 are not set.
• The battery voltage is more than 9 volts.
• The ignition switch is ON.
• The engine is running.
Condition for Setting the DTC • The ECM detects that the actual fuel rail pressure is lower than 15 MPa (2,180 psi) for longer than 5
seconds.
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 pilot injection. • 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 • An intermittently sticking FRP regulator may have allowed the fuel pressure to become low enough to
set this DTC.
• Normal Fuel Rail Pressure readings on the scan tool with the engine running in neutral at idle is
around 27 to 33 MPa (3,900 to 4,800 psi) after
warm up.
• A skewed FRP sensor value can set this DTC. The FRP Sensor on the scan tool should read 0.9 to
1.0 volt with the key ON and engine OFF after the
engine has stopped running for a minimum of 1
minute.
Notice: • This DTC most likely indicates a loss of fuel pressure by a fuel leak from the high pressure
side. Inspect the high pressure side fuel leakage
between the fuel supply pump and fuel injector
first.
• If the fuel tank is empty or near empty, air might be allowed to go into the fuel system. With air in the
fuel system, smooth flow of fuel into the supply
pump is interrupted and this DTC may set. Perform
bleeding of fuel system after refilling.
Schematic Reference: Fuel System Routing Diagram
and Engine Controls Schematics
Connector End View Reference: Engine Controls
Connector End Views or ECM Connector End Views
Circuit/ System Testing DTC P0093
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
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ISUZU KB P190 2007
Page 1759 of 6020

6E-142 ENGINE CONTROL SYSTEM (4JK1/4JJ1)
DTC P0234 (Flash Code 42)
Circuit Description
The boost pressure sensor is located in the air
induction tubing. The sensor is a transducer that varies
voltage according to changes in the air pressure inside
the air tubing. The ECM monitors the boost pressure
sensor signal for abnormal values. If the ECM detects
that the sensor signal is excessively high, this DTC will
set. This indicates excessive high boost pressure.
Condition for Running the DTC • DTCs P0045, P0107 and P0108 are not set.
• The ignition switch is ON.
• The engine is running.
Condition for Setting the DTC • The ECM detects that the actual boost pressure is more than 20 kPa (3 psi) over the desired boost
pressure under certain conditions for longer than
10 seconds.
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 pilot injection.
Condition for Clearing the DTC • Refer to DTC Type Definitions for Condition for Clearing the MIL/ DTC - Type A.
• The ECM limits fuel injection quantity.
• The ECM inhibits pilot injection. • The ECM inhibits cruise control.
Diagnostic Aids • An open circuit or high resistance in the boost pressure low reference circuit may set this DTC.
• Misrouted vacuum hoses may set this DTC.
• Check the turbocharger nozzle control actuator for a sticking. Refer to Turbocharger in the Engine
Mechanical section.
• Use a scan tool to verify the integrity of the boost pressure sensor signal. Compare the Boost
Pressure to the Desired Boost Pressure under all
load conditions for an excessively high value.
• The fuel with which gasoline was mixed may set this DTC.
Test Description
The numbers below refer to the step number on the
Circuit/ System Testing.
3. A skewed boost pressure sensor value (shifted to a
higher pressure) can set this DTC. The Boost Pressure
on the scan tool should read near Barometric Pressure
(BARO) with the key ON and engine OFF.
4. A skewed BARO sensor value (shifted to a lower
pressure) may indicate a wrong boost pressure. The
BARO on the scan tool should read near surrounding
barometric pressure.
Schematic Reference: Vacuum Hose Routing
Diagram and Engine Controls Schematics
Connector End View Reference: Engine Controls
Connector End Views or ECM Connector End Views
Circuit/ System Testing DTC P0234
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. Install a scan tool.
2. Turn OFF the ignition for 30 seconds.
3. Start the engine.
4. Monitor the DTC Information with a scan tool.
Is DTC P0045, P0107, P0108, P0638, P1196,
P1197, P1198, P2227, P2228 or P2229 also set? —
Go to Applicable DTC Go to Step 3
3 1. Turn ON the ignition, with the engine OFF.
2. Observe the Boost Pressure and Barometric Pressure (BARO) with a scan tool.
Does the scan tool indicate that the difference
between the Boost Pressure and BARO is more
than the specified value? 10 kPa (1.5
psi)
Go to Step 4 Go to Step 5
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ISUZU KB P190 2007
Page 1762 of 6020

ENGINE CONTROL SYSTEM (4JK1/4JJ1) 6E-145
DTC P0299 (Flash Code 65)
Circuit Description
The boost pressure sensor is located in the air
induction tubing. The sensor is a transducer that varies
voltage according to changes in the air pressure inside
the air tubing. The ECM monitors the boost pressure
sensor signal for abnormal values. If the ECM detects
that the sensor signal is excessively low, this DTC will
set. This indicates excessive low boost pressure.
Condition for Running the DTC • DTCs P0045, P0087, P0088, P0089, P0091, P0092, P0093, P0101, P0102, P0103, P0107,
P0108, P0116, P0117, P0118, P0122, P0123,
P0192, P0193, P0401, P0403, P0404, P0405,
P0406, P0638, P0652, P0653, P0698, P0699,
P1064, P1065, P1093, P1404, P2100, P2101,
P2103, P2227, P2228 and P2229 are not set.
• The ignition switch is ON.
• The engine is running.
• The fuel injection quantity is higher than a predetermined value.
Condition for Setting the DTC • The ECM detects that the actual boost pressure is more than 40 kPa (6 psi) below the desired boost
pressure under certain conditions for longer than
10 seconds.
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 cruise control. Condition for Clearing the DTC
• Refer to DTC Type Definitions for Condition for Clearing the MIL/ DTC - Type A.
Diagnostic Aids • Induction air leakage can cause a low boost pressure condition. A whistling noise may be heard
if a component is allowing air to enter the induction
system.
• Check for cracked air tubing that may only open during certain engine movement conditions.
• Misrouted vacuum hoses may set this DTC.
• Check the turbocharger nozzle control actuator for a sticking. Refer to Turbocharger in the Engine
Mechanical section.
• Use a scan tool to verify the integrity of the boost pressure sensor signal. Compare the Boost
Pressure to the Desired Boost Pressure under all
load conditions for an excessively low value.
• Loss of vacuum pressure or vacuum pump problem sets this DTC.
Test Description
The numbers below refer to the step number on the
diagnostic table.
4. A skewed boost pressure sensor value (shifted to a
lower pressure) can set this DTC. The Boost Pressure
on the scan tool should read near Barometric Pressure
(BARO) with the key ON and engine OFF.
5. A skewed BARO sensor value (shifted to a higher
pressure) may indicate a wrong boost pressure. The
BARO on the scan tool should read near surrounding
barometric pressure.
Schematic Reference: Vacuum Hose Routing
Diagram and Engine Controls Schematics
Connector End View Reference: Engine Controls
Connector End Views or ECM Connector End Views
Circuit/ System Testing DTC P0299
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. Install a scan tool.
2. Turn OFF the ignition for 30 seconds.
3. Start the engine.
4. Monitor the DTC Information with a scan tool.
Is DTC P0045, P0107, P0108, P2227, P2228 or
P2229 also set? —
Go to Applicable DTC Go to Step 3
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ISUZU KB P190 2007
Page 1830 of 6020

ENGINE CONTROL SYSTEM (4JK1/4JJ1) 6E-213
DTC P0661 or P0662 (Flash Code 58)
Circuit Description
The ECM controls the swirl levels, which energize the
swirl control solenoid valve based on the engine
running condition. The ECM commands the swirl
control solenoid valve to apply vacuum pressure to the
diaphragm actuator to operate swirl control butterflies
that is provided each intake port. If the ECM detects an
open circuit or short circuit on the solenoid valve circuit,
DTC P0661 or P0662 will set.
Condition for Running the DTC • The battery voltage is more than 9 volts.
• The ignition switch is ON.
Condition for Setting the DTC • The ECM detects a low voltage condition on the swirl control solenoid valve circuit when the
solenoid is commanded OFF. (DTC P0661)
• The ECM detects a high voltage condition on the swirl control solenoid valve circuit when the
solenoid is commanded ON. (DTC P0662)
Action Taken When the DTC Sets • The ECM illuminates the SVS lamp when the diagnostic runs and fails. Refer to DTC Type
Definitions for Action Taken When the DTC Sets -
Type C. (Euro 4 Specification) • 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.
(Except Euro 4 Specification)
• The ECM limits fuel injection quantity. (DTC P0661)
• The ECM inhibits cruise control. (DTC P0661)
Condition for Clearing the DTC • Refer to DTC Type Definitions for Condition for Clearing the SVS Lamp/ DTC - Type C. (Euro 4
Specification)
• Refer to DTC Type Definitions for Condition for Clearing the MIL/ DTC - Type A. (Except Euro 4
Specification)
Diagnostic Aids • If an intermittent condition is suspected, refer to Intermittent Conditions in this section.
Schematic Reference: Vacuum Hose Routing
Diagram and Engine Controls Schematics
Connector End View Reference: Engine Controls
Connector End Views or ECM Connector End Views
Circuit/ System Testing DTC P0661
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. Install a scan tool.
2. Turn OFF the ignition for 30 seconds.
3. Turn ON the ignition, with the engine OFF.
4. Monitor the DTC Information with a scan tool.
Does the DTC fail this ignition? —
Go to Step 3 Go to Diagnostic
Aids
3 1. Turn OFF the ignition.
2. Disconnect the swirl control solenoid valve harness connector.
3. Connect a test lamp between the ignition voltage feed circuit (pin 2 of E-67) and a
known good ground.
4. Turn ON the ignition, with the engine OFF.
Does the test lamp illuminate? —
Go to Step 4 Go to Step 6
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ISUZU KB P190 2007
Page 1843 of 6020

6E-226 ENGINE CONTROL SYSTEM (4JK1/4JJ1)
DTC P1093 (Flash Code 227)
Description
The common rail fuel system is comprised of two fuel
pressure sections: a suction side between the fuel tank
and the fuel supply pump and a high-pressure side
between the fuel supply pump and the fuel injectors.
Fuel is drawn from the fuel tank via a feed pump and
then pumped into the fuel rail by two plungers, all of
which are internal to the fuel supply pump. This high
pressure is regulated by the ECM using the fuel rail
pressure (FRP) regulator dependant upon values from
the FRP sensor attached to the fuel rail. If the ECM
detects that the fuel rail pressure is certain pressure
lower than the desired pressure, this DTC will set.
Condition for Running the DTC • DTC P0087, P0091, P0092, P0192, P0193, P0652, P0653, P0201 - P0204, P1064, P1065,
P124B and P2146 - P2151 are not set.
• The battery voltage is more than 9 volts.
• The ignition switch is ON.
• The engine is running.
• The FRP regulator commanded fuel flow is more than a threshold.
Condition for Setting the DTC • The ECM detects that the actual fuel rail pressure is more than 10 to 20 MPa (1,450 to 2,900 psi)
below the desired pressure for longer than 5
seconds.
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 pilot injection.
• 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 • An intermittently sticking FRP regulator may have allowed the fuel pressure to become low enough to
set this DTC.
• Normal Fuel Rail Pressure readings on the scan tool with the engine running in neutral at idle is
around 27 to 33 MPa (3,900 to 4,800 psi) after
warm up.
• A skewed FRP sensor value can set this DTC. The FRP Sensor on the scan tool should read 0.9 to
1.0 volt with the key ON and engine OFF after the
engine has stopped running for a minimum of 1
minute.
Notice: • This DTC most likely indicates a loss of fuel pressure by a restricted suction side fuel line.
Inspect the suction side fuel restriction between
the fuel supply pump and the fuel tank.
• If the fuel tank is empty or near empty, air might be allowed to go into the fuel system. With air in the
fuel system, smooth flow of fuel into the supply
pump is interrupted and this DTC may set. Perform
bleeding of fuel system after refilling.
Schematic Reference: Fuel System Routing Diagram
and Engine Controls Schematics
Connector End View Reference: Engine Controls
Connector End Views or ECM Connector End Views
Circuit/ System Testing DTC P1093
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. Install a scan tool.
2. Turn OFF the ignition for 30 seconds.
3. Start the engine.
4. Monitor the DTC Information with a scan tool.
Is DTC P0087, P0091, P0092, P0192, P0193,
P0201 - P0204, P1064, P1065, P1094, P124B or
P2146 - P2151 set? —
Go to Applicable DTC Go to Step 3
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ISUZU KB P190 2007
Page 1849 of 6020

6E-232 ENGINE CONTROL SYSTEM (4JK1/4JJ1)
Notice:• This DTC most likely indicates a loss of fuel pressure by a fuel leak from the high pressure
side. Inspect the high pressure side fuel leakage
between the fuel supply pump and fuel injector
first. • If the fuel tank is empty or near empty, air might be
allowed to go into the fuel system. With air in the
fuel system, smooth flow of fuel into the supply
pump is interrupted and this DTC may set. Perform
bleeding of fuel system after refilling.
Schematic Reference: Fuel System Routing Diagram
and Engine Controls Schematics
Connector End View Reference: Engine Controls
Connector End Views or ECM Connector End Views
Circuit/ System Testing DTC P1094
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. Inspect the high pressure side between the
fuel supply pump and the fuel injectors for fuel
leakage. The following components may
contain an external leak.
• Fuel supply pump
• Fuel rail
• Pressure limiter valve
• Fuel rail pressure (FRP) sensor
• Fuel pipe between the fuel supply pump and fuel rail
• Fuel pipe between the fuel rail and fuel injectors
• Each fuel pipe sleeve nuts
Notice: Fuel may leak under the cylinder head
cover from the inlet high pressure line. In such
case, the engine oil level will rise. Inspect for fuel
leakage into the engine oil.
Notice: Remove and inspect the inlet high
pressure joint to the fuel injectors for fuel leaking
from the sleeve nut(s). Replace the fuel injector
and injection pipe when foreign material was in
contact.
2. Repair any fuel system leaks as necessary.
Did you find and correct the condition? —
Go to Step 19 Go to Step 3
3 1. Remove each glow plug from the cylinder
head.
2. Inspect for fuel leakage into the combustion chamber.
Is there a cylinder that fuel leakage into the
combustion chamber? —
Go to Step 15 Go to Step 4
4 1. Install a scan tool.
2. Turn OFF the ignition for 30 seconds.
3. Start the engine.
4. Monitor the DTC Information with a scan tool.
Is DTC P0087, P0091, P0092, P0192, P0193,
P0201 - P0204, P1064, P1065, P124B or P2146 -
P2151 set? —
Go to Applicable DTC Go to Step 5
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ISUZU KB P190 2007