key ISUZU KB P190 2007 Workshop Service Manual

ENGINE CONTROL SYSTEM (4JK1/4JJ1) 6E-95
DTC P0101 (Flash Code 92)
Circuit Description
The mass air flow (MAF) sensor is an air flow meter
that measures the amount of air that enters the engine.
It is fitted between the air cleaner and turbocharger. A
small quantity of air that enters the engine indicates
deceleration or idle speed. A large quantity of air that
enters the engine indicates acceleration or a high load
condition. The ECM will calculate a predicted MAF
value and compares the actual MAF sensor voltage
signal to the predicted MAF value. This comparison will
determine if the signal is stuck, or is too low or too high
for a given operating condition. If the ECM detects that
the actual MAF sensor signal voltage is not within a
predetermined range of the calculated MAF value, this
DTC will set.
Condition for Running the DTC • DTCs P0045, P0102, P0103, P0107, P0108, P 0 11 2 , P 0 11 3 , P 0 11 6 , P 0 11 7 , P 0 11 8 , P 0 1 2 2 ,
P0123, P0234, P0403, P0404, P0405, P0406,
P0638, P0652, P0653, P0698, P0699, P1404,
P2100, P2101, P2103, P2227, P2228 and P2229
are not set.
AND following conditions are met longer than 10
seconds.
• The battery voltage is between 10.0 to 16.0 volts.
• The ignition switch is ON.
• The intake air temperature is less than 110 °C
(230 °F).
• The engine coolant temperature is between 0 to 11 0 °C (32 to 230 °F).
• The engine speed is between 850 to 3700 RPM.
• The EGR control is commanded OFF.
• The intake throttle control is commanded OFF.
• The commanded fuel injection quantity is OFF (accelerator pedal is not depressed).
• The engine run time is longer than 5 seconds. Condition for Setting the DTC
• The ECM detects that the MAF sensor signal voltage is not within a predetermined range of the
calculated MAF value 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.
• 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 • Any unmetered air that enters the engine downstream of the MAF sensor will cause this
DTC to set.
• High resistance in the MAF sensor circuit will set this DTC.
• A short between the signal circuit of the MAF sensor and the signal circuit of the intake air
temperature (IAT) sensor will skew the MAF
sensor lower than normal at higher air flows.
Notice: • The MAF Sensor parameter on scan tool will only update with engine running or one time after the
key is cycled when the ignition has been turned
OFF for longer than 10 seconds.
Schematic Reference : Engine Controls Schematics
Connector End View Reference : Engine Controls
Connector End Views or ECM Connector End Views
Circuit/ System Testing DTC P0101
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

6E-98 ENGINE CONTROL SYSTEM (4JK1/4JJ1)
DTC P0102 or P0103 (Flash Code 91)
Circuit Description
The mass air flow (MAF) sensor is an air flow meter
that measures the amount of air that enters the engine.
It is fitted between the air cleaner and turbocharger. A
small quantity of air that enters the engine indicates
deceleration or idle speed. A large quantity of air that
enters the engine indicates acceleration or a high load
condition. The sensor has the following circuits.
• Ignition voltage circuit
• Low reference circuit
• MAF sensor signal circuit
The ECM monitors the MAF sensor signal voltage. This
output voltage will display on the scan tool as a voltage
parameter and as a grams per second (g/s) parameter.
If the ECM detects an excessively low or high signal
voltage, DTC P0102 or P0103 will set.
Condition for Running the DTC • The battery voltage is between 11.5 to 16.0 volts.
• The ignition switch is ON.
• The engine is running.
Condition for Setting the DTC • The ECM detects that the MAF sensor signal voltage is less than 0.1 volts. (DTC P0102)
• The ECM detects that the MAF sensor signal voltage is more than 4.9 volts for 3 seconds. (DTC
P0103)
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 uses a MAF substitution of default value.
• The ECM limits fuel injection quantity.
• The ECM inhibits pilot injection.
• 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 • If an intermittent condition is suspected, refer to Intermittent Conditions in this section.
Notice: • The MAF Sensor parameter on scan tool will only update with engine running or one time after the
key is cycled when the ignition has been turned
OFF for longer than 10 seconds.
Test description
The number below refers to the step number on the
Circuit/ System Testing.
DTC P0102
4. This step tests for proper operation of the circuit in
the signal circuit. If the fuse in the jumper opens when
you perform this test, the signal circuit is shorted to
ground or low reference circuits.
Schematic Reference: Engine Controls Schematics
Connector End View Reference: Engine Controls
Connector End Views or ECM Connector End Views
Circuit/ System Testing DTC P0102
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. Observe the Mass Air Flow (MAF) Sensor parameter with a scan tool.
Is the MAF Sensor parameter less than the
specified value? 0.1 volts
Go to Step 3 Go to Diagnostic
Aids

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ISUZU KB P190 2007

ENGINE CONTROL SYSTEM (4JK1/4JJ1) 6E-137
DTC P0219 (Flash Code 543)
Circuit Description
The crankshaft position (CKP) sensor is located on the
left-hand of the cylinder block rear and it is behind the
starter motor. The ECM calculates the engine speed
and exact position of the crankshaft based on the
signal pulse from the CKP sensor. If the ECM detects
an engine overrun condition, this DTC will set.
Condition for Setting the DTC • The ECM detects that the engine speed is more than 4900 RPM (4JK1 standard output) or 4700
RPM (4JK1 high output and 4JJ1).
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.
• 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 • 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 • Make sure the CKP sensor is tight and the teeth are not damaged.
• Electromagnetic interference in the CKP sensor circuits may set this DTC.
• The Total Engine Overspeed Events parameter on scan tool indicates number of overrun events.
Notice: • This DTC is caused by an engine overspeed condition, which was most likely caused by driver
error (i.e. downshifting a manual transmission on a
steep grade). Excessive engine overspeed may
damage internal engine components.
Circuit/ System Testing DTC P0219
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 Important:
If DTC P0335 or P0336 is set, diagnose
that DTC first.
1. Install a scan tool.
2. Start the engine.
3. Observe the Engine Speed parameter with a scan tool.
4. Accelerate the engine as necessary.
Does the Engine Speed parameter ever exceed the
specified value? 5000 RPM
Go to Step 4 Go to Step 3
3 Ask the driver if overrun is caused by gear slip-out,
shift error, down-slope driving, etc. If engine
overrun has experienced, the engine must be
inspected and repaired as necessary.
Did you complete the action? —
Go to Step 6
—

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ISUZU KB P190 2007

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

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

6E-194 ENGINE CONTROL SYSTEM (4JK1/4JJ1)
DTC P0601 (Flash Code 53)
Circuit Description
This diagnostic applies to internal microprocessor
integrity conditions within the ECM.
Condition for Setting the DTC • The ECM detects that the calculated checksum does not agree with the ECM internal registered
checksum.
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.
• 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 • 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)
Circuit/ System Testing DTC P0601
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 Step 4
3 Important:
Replacement ECM must be
programmed and learned.
Replace the ECM. Refer to ECM Replacement.
Did you complete the replacement? —
Go to Step 4
—
41. Clear the DTCs with a scan tool.
2. Turn OFF the ignition for 30 seconds.
3. Start the engine.
4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the
vehicle within the conditions that you
observed from the Freeze Frame/ Failure
Records.
Did the DTC fail this ignition? —
Go to Step 3 Go to Step 5
5 Observe the DTC Information with a scan tool.
Are there any DTCs that you have not diagnosed? —
Go to DTC List System OK

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ISUZU KB P190 2007

ENGINE CONTROL SYSTEM (4JK1/4JJ1) 6E-197
DTC P0604 or P0606 (Flash Code 153 or 51)
Circuit Description
This diagnostic applies to internal microprocessor
integrity conditions within the ECM.
Condition for Setting the DTC • The ECM detects a malfunction in its internal random access memory (RAM). (DTC P0604)
• The ECM detects a malfunction in its internal main central processing unit (CPU) or sub integrated
circuit (IC). (DTC P0606)
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
P0604)
• The ECM inhibits pilot injection. (DTC P0604)
• The ECM inhibits cruise control. (DTC P0604)
• 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. (DTC P0604)
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)
Circuit/ System Testing DTC P0604 or P0606
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 Step 4
3 Important:
Replacement ECM must be
programmed and learned.
Replace the ECM. Refer to ECM Replacement.
Did you complete the replacement? —
Go to Step 4
—
41. Clear the DTCs with a scan tool.
2. Turn OFF the ignition for 30 seconds.
3. Start the engine.
4. Operate the vehicle within the Conditions for Running the DTC. You may also operate the
vehicle within the conditions that you
observed from the Freeze Frame/ Failure
Records.
Did the DTC fail this ignition? —
Go to Step 3 Go to Step 5
5 Observe the DTC Information with a scan tool.
Are there any DTCs that you have not diagnosed? —
Go to DTC List System OK

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ISUZU KB P190 2007

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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ENGINE CONTROL SYSTEM (4JK1/4JJ1) 6E-231
DTC P1094 (Flash Code 226)
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 difference between the
actual and the desired fuel pressure is small at low
engine speed but the FRP regulator commanded fuel
flow is certain amount high, this DTC will set. (FRP
Regulator Commanded High DTC)
If the ECM detects that the fuel rail pressure is sharply
decreased when fuel cut, this DTC will also set. (Fuel
Pressure Drop DTC)
Condition for Running the DTC
FRP Regulator Commanded High DTC • DTCs P0087, P0091, P0092, P0117, P0118, P0182, P0183, P0192, P0193, P0500, P0501,
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 accelerator pedal is not depressed.
• The engine coolant temperature is more than 50 °C
(122 °F).
• The vehicle speed is less than 3km/h (2MPH).
Fuel Pressure Drop DTC
• DTCs P0087, P0091, P0092, P0182, P0183, 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 accelerator pedal is not depressed.
• The engine speed is more than 1500RPM.
• The vehicle speed is more than 3km/h (2MPH).
Condition for Setting the DTC
FRP Regulator Commanded High DTC • The ECM detects that the FRP regulator commanded fuel flow is more than a
predetermined range for longer than 10 seconds
when the engine speed is near idle speed.
Fuel Pressure Drop DTC
• The ECM detects that the fuel rail pressure is dropped more than a threshold when the
commanded fuel is cut. Action Taken When the DTC Sets
FRP Regulator Commanded High DTC • 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.
Fuel Pressure Drop DTC
• 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
FRP Regulator Commanded High DTC • Refer to DTC Type Definitions for Condition for Clearing the MIL/ DTC - Type A.
Fuel Pressure Drop 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 • 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.

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6E-328 ENGINE CONTROL SYSTEM (4JK1/4JJ1)
Hard Start
ChecksAction
Definition:
The engine cranks OK, but does not start for a long time. The engine does eventually run, or may start but immediately dies.
Preliminary Checks • Diagnostic System Check - Engine Controls.
• Ensure the driver is using the correct starting procedure.
• Inspect the ECM grounds for being clean, tight, and in their proper locations.
• Inspect that the harness connectors are correctly connected.
• Inspect the fuel type and quality.
• Inspect the programmed fuel injector ID code for each cylinder.
• Inspect the Scan Tool Data List in this section.
• Inspect the Service Bulletin.
Sensor Checks Inspect the engine control sensors for the following conditions. Refer to the Scan Tool
Data List in this section.
• Compare the Coolant Temperature with the Intake Air Temperature (IAT) and Fuel Temperature (FT) parameters 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 in each circuit or for a skewed sensor.
Notice: The mass air flow (MAF) sensor is heated and as a result the IAT may indicate
a higher than normal intake air temperature if the ignition switch is being ON.
• Observe the Fuel Rail Pressure (FRP) Sensor parameter with the engine OFF. The FRP Sensor 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. If not, check for high
resistance in each circuit or for a skewed sensor.
• Crankshaft position (CKP) sensor is tight and the sensor rotor is not damaged.
• Camshaft position (CMP) sensor is tight and the timing chain sprocket is not damaged.
Fuel System Checks Inspect the fuel system for the following conditions. Refer to Fuel System Check chart
and appropriate procedure in the Fuel System section.
• Air in the fuel system.
• Water contamination in the fuel.
• Fuel waxing or icing.
• Fuel filter indicator lamp is continuously or frequently turned ON with engine run.
• External fuel leaks or high engine oil level.
• In-tank fuel pump operation. Refer to In-tank Fuel Pump System Check in this section.
• Fuel leak off from the fuel pressure limiter valve and fuel injectors.
• Fuel lines between the fuel tank and fuel supply pump for being crushed, kinked, tightness, cracks and plugged.
• A plugged fuel tank vent valve and hose.
• Inside the fuel tank for any foreign material that may be getting drawn into the fuel line pickup causing a blocked condition.
• Fuel supply pump operation.
Notice: The fuel supply pump must be timed to the engine and adjustment value must
be learned to the ECM.
• Perform the Cylinder Balance Test with a scan tool.
• Perform the Injector Force Drive with a scan tool.
• Observe the FRP Regulator Feedback current on the scan tool.

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ISUZU KB P190 2007