6E-20 Engine Control System (4JH1)
1
Legend
1. Engine Control Module (ECM)
2 1
Legend
1. Engine Coolant Temperature (ECT) Sensor
2. Thermo Unit for W ater Temperature Gauge
2
3 14
Legend
1. EGR Solenoid Valve
2. To Vacuum Pump
3. To EGR Valve
4. To Intake Duct
2 1
Legend
1. Crankshaft Position (CKP) Sensor
2. Clutch Housing
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ISUZU KB P190 2007
Engine Control System (4JH1) 6E-27
Engine Coolant Temperature Coolant (ECT) Sensor
LNW 46ESH003901
Connector No. E-41
Connector Color Gray
Test Adapter No. J-35616-4A
Pin W ire Color Pin Function
1 GRY ECT Sensor Signal
2 BLK/PNK ECT Sensor Low Reference
Fuel Injection Pump Control Unit (PCU)
RTW 66ESH000701
Connector No. E-6
Connector Color Black
Test Adapter No. J-35616-8
Pin W ire Color Pin Function
1 RED CAN Low Signal
2 YEL CAN High Signal
3
Not Used
Connector No. E-6
Connector Color Black
Test Adapter No. J-35616-8
Pin W ire Color Pin Function
4
Not Used
5 ORN Engine Shutoff (ESO) Solenoid
Valve Control Signal Input
6 BLK Ground
7 BLU/RED Battery voltage
8 PNK CKP Sensor Signal Input
9
Not Used
Glow Plug
LNW 46ESH000701
Connector No. E-49
Connector Color Silver
Pin W ire Color Pin Function
1 BLK/RED Power Supply
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ISUZU KB P190 2007
6E-36 Engine Control System (4JH1)
Scan Tool Data List
The scan tool Data List contains all engine related
parameters that are available on the scan tool. Use the
scan tool Data List only after the following is
determined: • The Diagnostic System Check - Engine Controls is
completed.
• No diagnostic trouble codes (DTCs) are present.
• On-board diagnostics are functioning properly.
The scan tool values from a properly running engine
may be used for comparison with the engine you are
diagnosing. The scan tool Data List represents values
that would be seen on a normal running engine.
Important:
A scan tool that displays faulty data should not be used.
The scan tool problem should be reported to the
manufacturer. Use of a faulty scan tool can result in
misdiagnosis and unnecessary parts replacement. Onl
y
the parameters listed below are referenced in this
service manual for use in diagnosis.
Scan Tool Parameter Units DisplayedTypical Data Value at
Engine Idle
Typical Data Value at 2000
RPM
Operating Conditions: Engine Idling or 2000 RPM / Engine Coolant Temperature is between 75-85 °C (167-185 °F) /
Accelerator Pedal is Constant / Park or Neutral / Accessories OFF / Vehicle Located at Sea Level
Ignition Switch On/Off On On
System Voltage V 11.0 – 15.0 11.0 – 15.0
ECM Main Relay On/Off On On
Engine Speed RPM 650 - 750 1950 – 2050
Desired Idle Speed RPM 700 700
Injection Pump Speed RPM 325 - 375 975 – 1025
Accelerator Pedal Position % 0.0 5.0 – 7.0
Idle Switch On/Off On Off
Intake Air Temperature °C/°F 20 – 40°C / 68 – 104°F 20 – 40°C / 68 – 104°F
Engine Coolant Temperature °C/°F 75 - 85 °C / 167 - 185 °F 75 - 85 °C / 167 - 185 °F
Fuel Temperature °C/°F 20 – 60°C / 68 – 140°F 20 – 60°C / 68 – 140°F
Barometric Pressure hPa Nearly 1010 hPa at sea level Nearly 1010 hPa at sea level
Vacuum Pressure Sensor hPa Nearly 2020 hPa at sea level Nearly 2020 hPa at sea level
Turbocharger Solenoid Command % 100% at sea level 100% at sea level
EGR Solenoid Command % Nearly 90% Nearly 90%
Mass Air Flow Sensor mg/strk
More than 430 mg/strk at sea
level (with EGR system)
More than 700 mg/strk at sea
level (without EGR system)
More than 430 mg/strk at sea
level (with EGR system)
More than 700 mg/strk at sea
level (without EGR system)
Desired Mass Air Flow mg/strk
More than 430 mg/strk at sea
level (with EGR system)
1500 mg/strk (without EGR
system)
More than 430 mg/strk at sea
level (with EGR system)
1500 mg/strk (without EGR
system)
Actual Injection Quantity mg/strk 6.0 – 9.0 7.0 – 11.0
Desired Injection Quantity mg/strk 6.0 – 9.0 7.0 – 11.0
Actual Injection Timing °CA 1.0 – 4.0 3.0 – 4.5
Desired Injection Timing °CA 1.0 – 4.0 3.0 – 4.5
Neutral Switch On/Off On On
Brake Pedal 1 Switch Applied/ ReleasedReleased Released
Brake Pedal 2 Switch Applied/ ReleasedReleased Released
Clutch Pedal Switch Applied/ ReleasedReleased Released
Vehicle Speed km/h / MPH 0 0
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ISUZU KB P190 2007
Engine Control System (4JH1) 6E-37
Scan Tool Parameter Units DisplayedTypical Data Value at
Engine Idle
Typical Data Value at 2000
RPM
Glow Relay Command On/Off Off Off
Glow Indicator Lamp Command On/Off Off Off
Malfunction Indicator Lamp (MIL) Command On/Off Off Off
A/C Request Signal On/Off Off Off
A/C Relay Command On/Off Off Off
Scan Tool Data Definitions
A list of each message displayed on the scan tool will
be explained in Engine Controls. This information will
assist in emission or driveability problems. The displays
can be viewed while the vehicle is being driven. Always
perform the Diagnosis System Check – Engine Controls
first. The Diagnostic System Check will confirm prope
r
system operation.
Ignition Switch
This parameter displays the input status of the ignition
switch to the ECM terminal (pin 39). The scan tool will
display On or Off. On indicates the ignition switch is
turned ON position.
System Voltage
This parameter displays the system voltage measured
by the ECM terminal (pin 3) at the voltage feed from the
ECM main relay.
ECM Main Relay
This parameter displays the commanded state of the
ECM main relay control circuit (pin 58). The scan tool
will display On or Off. On indicates the ECM main rela
y
control circuit is being grounded by the ECM, allowing
the main relay to supply voltage to the other circuits o
f
the ECM. Off indicates the main relay is not being
commanded On by the ECM.
Engine Speed
This parameter displays the speed of the crankshaft as
calculated by the ECM based on input from the
crankshaft position (CKP) sensor or camshaft position
(CMP) sensor. The scan tool will display the engine
speed in revolution per minute (RPM).
Desired Idle Speed
This parameter displays the idle speed requested by the
ECM. The ECM will compensate for various engine
loads based on engine coolant temperature (ECT) and
A/C system status. If the A/C system is activated, the
ECM sets 100 RPM higher than normal idle speed.
Injection Pump Speed
This parameter displays the speed of the injection pump
as calculated by the fuel injection pump control unit
(PCU) based on the input from the fuel injection pump
camshaft position (CMP) sensor. The scan tool will
display the injection pump speed in revolution pe
r
minute (RPM).
Accelerator Pedal Position
This parameter displays the angle of the accelerato
r
pedal as calculated by the ECM using the signal from
the accelerator pedal position (APP) sensor. The
accelerator pedal position indicated angle is a range o
f
values indicating a low percentage when the accelerator
pedal is not depressed to a high percentage when the
accelerator pedal is fully depressed.
Idle Switch
This parameter displays the input status of the idle
switch to the ECM terminal (pin 69). The Tech will
display On or Off. On indicates the accelerator pedal is
not being pushed down. Off indicates the accelerato
r
pedal is being depressed.
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ISUZU KB P190 2007
6E-38 Engine Control System (4JH1)
Intake Air Temperature
This parameter displays the temperature of the intake
air based on a voltage input from the intake ai
r
temperature (IAT) sensor to the ECM. The scan tool will
display a low temperature when signal voltage is high,
and high temperature when the signal voltage is low.
Note that the IAT sensor is internal to the mass air flo
w
(MAF) sensor and the MAF sensor is heated.
Engine Coolant Temperature
This parameter displays the temperature of the engine
coolant based on a voltage input from the engine
coolant temperature (ECT) sensor to the ECM. The
scan tool will display a low temperature when the signal
voltage is high, and a high temperature when the signal
voltage is low.
Fuel Temperature
This parameter displays the temperature of the fuel as
calculated by the fuel injection pump control unit (PCU)
using the signal from the fuel temperature sensor inside
of the PCU.
Barometric Pressure
This parameter displays the barometric pressure as
calculated by the ECM using the signal from the
barometric pressure (BARO) sensor inside of the ECM.
Vacuum Pressure Sensor (High altitude
specification only)
This parameter displays the amount of the vacuum
pressure to the turbocharger wastegate valve. W hen a
high vacuum pressure at a low vacuum pressure
amount to the turbocharger wastegate valve. The scan
tool will display doubled barometric pressure when the
ignition is ON with the engine OFF.
Turbocharger Solenoid Command (High altitude
specification only)
This parameter displays the turbocharger solenoid
valuve control duty ratio commanded by the ECM
terminal (pin 96) using the signal from various senso
r
inputs. W hen a low duty ratio, vacuum pressure to the
turbocharger wastegate valve is controlled to increase.
W hen a high duty ratio, vacuum pressure to the
turbochager wastegate valve is controlled to reduce.
EGR Solenoid Command
This parameter displays the EGR solenoid valve control
duty ratio commanded by the ECM terminal (pin 97)
using the signal from engine speed, and injection
volume and various sensor inputs. W hen a small dut
y
ratio, the EGR valve is controlled to close. W hen a large
duty ratio, the EGR valve is controlled to open.
Mass Air Flow Sensor
This parameter displays the air flow into the engine as
calculated by the ECM based on the mass air flo
w
(MAF) sensor input. The scan tool will display a high
value at higher engine speeds, and a low value at idle.
This can be compared to the Desired Mass Air Flow to
determine MAF sensor accuracy, EGR problem o
r
intake problem. Note that the MAF on the scan tool will
only update with the engine running.
Desired Mass Air Flow
This parameter displays a mass air flow desired by the
ECM based on current driving condition.
Actual Injection Quantity
This parameter displays the injection quantity calculated
by the PCU based on the fuel injection solenoid valve
On time which compensated from the timing device
position and fuel temperature inputs. This can be
compared to the Desired Injection Quantity to determine
fuel system problem.
Desired Injection Quantity
This parameter displays an injection quantity desired b
y
the ECM based on current driving condition using target
injection maps.
Actual Injection Timing
This parameter displays the injection timing calculated
by the PCU based on the timing device position which
determined from the crankshaft position sensor and
camshaft position sensor inputs. This can be compared
to the Desired Injection Timing to determine timing
device problem or fuel system problem.
Desired Injection Timing
This parameter displays injection timing desired by the
ECM based on current driving condition using target
injection timing maps. This timing is compensated b
y
engine coolant temperature, altitude and intake ai
r
temperature, etc.
Neutral Switch
This parameter displays the state of the neutral switch
as determined by the ECM terminal (pin 87) based on
an input from the neutral switch or inhibitor switch.
Brake Pedal 1 Switch
This parameter displays the state of the brake pedal as
determined by the ECM terminal (pin 30) based on an
input from the brake pedal 1 switch. This switch turns
On the stop lamps when the brake pedal is depressed.
The scan tool will display Applied when the brake pedal
is depressed.
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ISUZU KB P190 2007
Engine Control System (4JH1) 6E-47
Engine Cranks but Does Not Run
Description
The Engine Cranks but Does Not Run diagnostic table
is an organized approach to identifying a condition that
causes an engine to not start. The diagnostic table
directs the service technician to the appropriate system
diagnosis. The diagnostic table assumes the following
conditions are met:
• The battery is completely charged and terminals
are cleaned and tight.
• The engine cranking speed is normal.
• There is adequate fuel in the fuel tank.
• There is no fuel leak in the fuel line.
• There is no air in the fuel line.
• Filters (Air, Fuel) are clean.
• Fuse and slow blow fuse are normal.
Diagnostic Aids
• If an intermittent condition is suspected, refer to
Intermittent Conditions in this section.
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 the scan tool. 2. Turn OFF the ignition for 30 seconds.
3. Crank the engine for specified amount of time.
4. Monitor the Diagnostic Trouble Code (DTC) Information with the scan tool.
Does the scan tool display any DTCs that failed this
ignition? 15 seconds
Go to Diagnostic
Trouble Code (DTC) List Go to Step 3
3 1. Check for normal readings at key up for the
following inputs and output: Refer to the scan
tool Data List or a known good vehicle to
determine normal values. • System Voltage
• Engine Coolant Temperature (ECT)
• Intake Air Temperature (IAT)
• Mass Air Flow (MAF) Sensor
• Barometric Pressure
• Desired Injection Quantity
2. Repair or replace as necessary.
Did you find and correct the condition?
Go to Step 10 Go to Step 4
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ISUZU KB P190 2007
Engine Control System (4JH1) 6E-51
DTC
(Symptom Code) Flash
Code MIL
Status DTC Name on
scan tool Condition for
Running the DTC Condition for
Setting the DTC Possible Cause
P0105
(2) 34 ON Vacuum Pressure
Sensor Circuit Low
Voltage •
The ignition switch
is ON. •
The ECM detects
that the vacuum
pressure sensor
signal voltage is
less than 0.5 volts
for 3 seconds. •
Sensor 5V reference circuit is
open circuit or high resistance,
short to ground or short to the
low reference circuit.
• Sensor signal circuit is open
circuit, high resistance, short to
ground or short to the low
reference circuit.
• Poor harness connector
connection.
• Faulty vacuum pressure sensor.
• Faulty ECM.
P0105 (7) 34 ON Vacuum Pressure
Sensor Voltage 5V
Reference Circuit
High Voltage
•
The ignition switch
is ON. •
The ECM detects
that the vacuum
pressure sensor 5
volts reference
circuit voltage is
more than 5.2 volts
for 2.5 seconds.
•
Sensor 5V reference circuit is
short to battery or ignition
voltage.
• Faulty ECM.
P0105 (9) 34 ON Vacuum Pressure
Sensor Voltage 5V
Reference Circuit
Low Voltage
•
The ignition switch
is ON. •
The ECM detects
that the vacuum
pressure sensor 5
volts reference
circuit voltage is
less than 4.5 volts
for 2.5 seconds.
•
Sensor 5V reference circuit is
short to ground or short to low
reference circuit.
• Faulty vacuum pressure sensor.
• Faulty ECM.
P0110 (1) 23 ON Intake Air
Temperature (IAT)
Sensor Circuit
High Voltage •
The ignition switch
is ON.
•
The ECM detects
that the IAT sensor
signal voltage is
more than 4.7 volts
for 3 seconds. •
Sensor signal circuit is open
circuit, high resistance, short to
any 5V reference circuit, short to
battery or ignition voltage.
• Sensor low reference circuit is
open circuit or high resistance.
• Poor harness connector
connection.
• Faulty IAT sensor.
• Faulty ECM.
P0110 (2) 23 ON Intake Air
Temperature (IAT)
Sensor Circuit Low
Voltage
•
The ignition switch
is ON.
•
The ECM detects
that the IAT sensor
signal voltage is
less than 0.3volts
for 3 seconds.
•
Sensor signal circuit is short to
ground or short to the low
reference circuit.
• Faulty IAT sensor.
• Faulty ECM.
P0115
(1) 14 ON Engine Coolant
Temperature
(ECT) Sensor
Circuit High
Voltage •
The ignition switch
is ON.
•
The ECM detects
that the ECT sensor
signal voltage is
more than 4.7 volts
for 3 seconds. •
Sensor signal circuit is open
circuit, high resistance, short to
any 5V reference circuit, short to
battery or ignition voltage.
• Sensor low reference circuit is
open circuit or high resistance.
• Poor harness connector
connection.
• Faulty ECT sensor.
• Faulty ECM.
P0115 (2) 14 ON Engine Coolant
Temperature
(ECT) Sensor
Circuit Low
Voltage
•
The ignition switch
is ON.
•
The ECM detects
that the ECT sensor
signal voltage is
less than 0.3volts
for 3 seconds. •
Sensor signal circuit is short to
ground or short to the low
reference circuit.
• Faulty ECT sensor.
• Faulty ECM.
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ISUZU KB P190 2007
6E-62 Engine Control System (4JH1)
DTC
(Symptom Code) Flash
Code MIL
Status DTC Name on
scan tool Condition for
Running the DTC Condition for
Setting the DTC Possible Cause
P1173
(3) 22 OFF Limitation of
Injection Quantity •
The ignition switch
is ON. •
The ECM detects
an excessive high
coolant temperature
for longer than 30
seconds.
•
Engine overheat.
• Faulty engine cooling system.
• Faulty ECT sensor.
P1173 (7) 22 OFF Limitation of
Injection Quantity
•
The ignition switch
is ON. •
The ECM detects
an excessive high
FT for longer than
30 seconds.
•
Faulty PCU.
P1173 (A) 22 OFF Limitation of
Injection Quantity
•
The ignition switch
is ON. •
The ECM detects
an excessive low
FT for longer than
30 seconds.
•
Faulty PCU.
P1335 (A) 43 ON Crankshaft
Position (CKP)
Sensor Circuit •
The ignition switch
is ON. •
The PCU detects
CKP sensor signal
from the ECM is
faulty.
•
CKP sensor signal output circuit
is open circuit, high resistance,
short to ground, short to battery
or ignition voltage.
• Poor harness connector
connection.
• Faulty PCU.
• Faulty ECM.
P1345 (A) 41 ON Crankshaft
Position (CKP) –
Camshaft Position
(CMP) Correlation
•
The PCU received
faulty fuel injection
pump CMP sensor
signal for 1 second.
•
Faulty fuel injection pump.
• Faulty PCU.
P1520 (A) 47 ON Park/Neutral
Position Switch
Circuit •
The ignition switch
is ON.
• The engine speed
is higher than 1500
RPM.
• The vehicle speed
is higher than 63
km/h (39 MPH)
(M/T) or 78 km/h
(49 MPH) (A/T).
• The clutch pedal is
released. (M/T)
•
The ECM detects
that the neutral
switch signal is
continuously ON
(neutral or P/N
range) during three
consecutive driving
cycles.
•
Manual Transmission
• Neutral switch signal circuit is
short to battery or ignition
voltage.
• Faulty neutral switch.
• Faulty ECM.
• Automatic Transmission
• P & N position switch signal
circuit is short to battery or
ignition voltage.
• Misadjusted inhibitor switch.
• Faulty inhibitor switch.
• Faulty ECM.
P1520 (B) 47 ON Park/Neutral
Position Switch
Circuit •
The ignition switch
is ON.
• The engine speed
is higher than 665
RPM
• The vehicle speed
is lower than 2 km/h
(1.2 MPH).
• The clutch pedal is
released after once
depressed.
•
The ECM detects
that the neutral
switch signal is
continuously OFF
(other than neutral)
during three
consecutive driving
cycles.
•
ECM (10A) fuse (EB-4) open.
• Neutral switch ignition voltage
feed circuit is open circuit or high
resistance.
• Neutral switch signal circuit is
open circuit or high resistance.
• Poor harness connector
connection.
• Faulty neutral switch.
• Faulty ECM.
P1605 (C) 55 ON Control Module
Internal
Performance •
The ECM detects
internal seed or key
file in EEPROM
data is destroyed.
•
Faulty ECM.
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ISUZU KB P190 2007