
6B – 18 ENGINE COOLING
110RS005
• Check the rubber hoses for swelling.
Installation
1. Install radiator assembly (9) with hose, taking care not to damage the radiator core with a fan blade.
2. Support the radiator upper tank with the bracket (5) and secure the radiator.
3. Connect reserve tank hose (6).
4. Install lower fan guide (3).
5. Connect radiator inlet hose and outlet hose (1) to the engine.
RTW 36BMH000101
6. Connect oil cooler hose to automatic transmission.
7. Connect battery ground cable.
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ISUZU KB P190 2007

6E-34 Engine Control System (4JH1)
Step Action Value(s) Yes No
2 1. Turn ON the ignition, with the engine OFF.
2. Attempt to establish communication with the listed control modules. • Engine control module (ECM)
• Transmission control module (TCM) (A/T
only)
• Electronic hydraulic control unit (EHCU)
Does the scan tool communicate with all the listed
control modules?
Go to Step 3 Go to scan tool
Does Not
Communicate with Keyword 2000 Device
3 Attempt to start the engine. Does the engine start and idle?
Go to Step 4 Go to Engine
Cranks but Does Not Run
4 Select the DTC display function for the following control modules: • ECM
• TCM (A/T only)
• EHCU
Does the scan tool display any DTCs?
Go to Step 5 Go to Step 12
5 1. Turn OFF the ignition for 30 seconds. 2. Start the engine.
3. Monitor the DTC Information with the scan tool.
Did you complete the action?
Go to Step 6
6 Does the scan tool display ECM DTC P0602?
Go to Applicable
DTC Go to Step 7
7 Does the scan tool display ECM DTC P0251 (Symptom Code 9 or A), P0606 (Symptom Code A
or B) or P1605 (Symptom Code C, D or E)?
Go to Applicable
DTC Go to Step 8
8 Does the scan tool display ECM DTC P0560 (Symptom Code 1, 2 or A)?
Go to Applicable
DTC Go to Step 9
9 Does the scan tool display following ECM DTC
P0561 (Symptom Code A or B) or P1625 (Symptom
Code A or B)?
Go to Applicable
DTC Go to Step 10
10 Does the scan tool display following ECM DTC P1650 (Symptom Code A or B) or P1651 (Symptom
Code A or B)?
Go to Applicable
DTC Go to Step 11
11 Is there any other code in any controller that has not
been diagnosed?
Go to Applicable
DTC Go to Step 12
12 Is the customer’s concern with the automatic
transmission? Go to Diagnostic
System Check Transmission Control Go to Step 13
13 Is the customer’s concern with the ABS system?
Go to Diagnostic
System Check Brake Control Go to Step 14
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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

Engine Control System (4JH1) 6E-157
DTC P0500 (Symptom Code 1, A) (Flash Code 24)
Circuit Description
The vehicle speed sensor (VSS) is used by the engine
control module (ECM) and speedometer, which
generates a speed signal from the transmission output
shaft. The VSS has the following circuits.
• Ignition voltage feed circuit
• VSS signal circuit
• VSS low reference circuit
The VSS uses a hall effect element. It interacts with the
magnetic field created by the rotating magnet and
outputs square wave pulse signal. The 12 volts
operating supply from the Meter fuse (except 2W D with
A/T) or Back Up fuse (2W D with A/T). The ECM
calculates the vehicle speed by the VSS. If the vehicle
is 2W D with automatic transmission, VSS signals are
sent from the transmission control module (TCM). If the
ECM detects VSS signals are generated with high
frequencies, this DTC will set.
Condition for Running the DTC
• The ignition switch is ON.
Condition for Setting the DTC
• The ECM detects that the vehicle speed is highe
r
than 200 km/h (125 MPH) for 5 seconds.
(Symptom Code 1)
•
The ECM detects that the vehicle speed senso
r
signal frequency is too high for 0.6 seconds.
(Symptom Code A)
Action Taken When the DTC Sets
• The ECM illuminates the malfunction indicato
r
lamp (MIL) when the diagnostic runs and fails.
• The ECM uses a vehicle speed substitution of 5
km/h (3 MPH) for engine control.
Condition for Clearing the MIL/DTC
• The ECM turns OFF the MIL when the diagnostic
runs and does not fail.
• A history DTC clears after 40 consecutive driving
cycles without a fault. Or clear with the scan tool.
Diagnostic Aids
• Electrical or magnetic interference may affect
intermittent condition.
• If an intermittent condition is suspected, refer to
Intermittent Conditions in this section.
DTC P0500 (Symptom Code 1, A) (Flash Code 24)
Schematic Reference: Engine Controls Schematics
Connector End View Reference: Engine Controls
Connector End Views or Engine Control Module (ECM)
Connector End Views
Chart for 2WD with A/T
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 all of the circuits going to the automatic transmission (A/T) vehicle speed sensor (VSS)
for the following: • Routed too closely to fuel injection solenoid
wiring or components
• Routed too closely to after-market add-on
electrical equipment
• Routed too closely to solenoids, relays, and
motors
2. If you find incorrect routing, correct the harness routing.
Did you find and correct the condition?
Go to Step 7 Go to Step 3
3 1. Turn OFF the ignition. 2. Disconnect the A/T VSS harness connector.
3. Inspect for an intermittent and for poor connections at the harness connector of the A/T
VSS (pins 1, 2 and 3 of E-30 connector).
4. Repair the connection(s) as necessary.
Did you find and correct the condition?
Go to Step 7 Go to Step 4
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ISUZU KB P190 2007

6E-158 Engine Control System (4JH1)
Step Action Value(s) Yes No
4 1. Turn OFF the ignition.
2. Disconnect the engine control module (ECM) harness connector.
3. Inspect for an intermittent and for a poor connection on A/T VSS circuit at the harness
connector of the ECM (pin 68 of C-56 connector).
4. Repair the connection(s) as necessary.
Did you find and correct the condition?
Go to Step 7 Go to Step 5
5 1. Remove the A/T VSS. Refer to A/T Speed Sensor Replacement in automatic transmission
section.
2. Visually inspect the A/T VSS for the following conditions: • Physical damage
• Being loose
• Improper installation
3. The following conditions may cause this DTC to set: • Electromagnetic interference in the A/T
VSS circuits
4. Repair or replace as necessary.
Did you find and correct the condition?
Go to Step 7 Go to Step 6
6 Replace the A/T VSS. Refer to A/T Speed Sensor Replacement in automatic transmission section
Did you complete the replacement?
Go to Step 7
7 1. Reconnect all previously disconnected harness
connector(s).
2. Clear the DTCs with the scan tool.
3. Turn OFF the ignition for 30 seconds.
4. Drive the vehicle.
5. Observe the Vehicle Speed parameter with the scan tool.
Does the Vehicle Speed parameter indicate correct
vehicle speed?
Go to Step 8 Go to Step 2
8 Observe the DTC Information with the scan tool. Are there any DTCs that you have not diagnosed? Go to Diagnostic
Trouble Code (DTC) List System OK
Chart for except 2WD with A/T
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 all of the circuits going to the vehicle speed sensor (VSS) for the following: • Routed too closely to fuel injection solenoid
wiring or components
• Routed too closely to after-market add-on
electrical equipment
• Routed too closely to solenoids, relays, and
motors
2. If you find incorrect routing, correct the harness routing.
Did you find and correct the condition?
Go to Step 7 Go to Step 3
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ISUZU KB P190 2007

6E-160 Engine Control System (4JH1)
DTC P0500 (Symptom Code B) (Flash Code 24)
Circuit Description
The vehicle speed sensor (VSS) is used by the engine
control module (ECM) and speedometer, which
generates a speed signal from the transmission output
shaft. The VSS has the following circuits.
• Ignition voltage feed circuit
• VSS signal circuit
• VSS low reference circuit
The VSS uses a hall effect element. It interacts with the
magnetic field created by the rotating magnet and
outputs square wave pulse signal. The 12 volts
operating supply from the Meter fuse (except 2W D with
A/T) or Back Up fuse (2W D with A/T). The ECM
calculates the vehicle speed by the VSS. If the vehicle
is 2W D with automatic transmission, VSS signals are
sent from the transmission control module (TCM). If the
ECM detects VSS signals are not generated, this DTC
will set.
Condition for Running the DTC
• The ignition switch is ON.
• The engine speed is higher than 3600 RPM.
• The fuel injection quantity is more than 41 mg/strk.
Condition for Setting the DTC
• The ECM detects that the vehicle speed is lowe
r
than 1.5 km/h (1 MPH) for 60 seconds.
Action Taken When the DTC Sets
• The ECM illuminates the malfunction indicato
r
lamp (MIL) when the diagnostic runs and fails.
Condition for Clearing the MIL/DTC
• The ECM turns OFF the MIL when the diagnostic
runs and does not fail.
• A history DTC clears after 40 consecutive driving
cycles without a fault. Or clear with the scan tool.
Diagnostic Aids
• Electrical or magnetic interference may affect
intermittent condition.
• If an intermittent condition is suspected, refer to
Intermittent Conditions in this section.
DTC P0500 (Symptom Code B) (Flash Code 24)
Schematic Reference: Engine Controls Schematics
Connector End View Reference: Engine Controls
Connector End Views or Engine Control Module (ECM)
Connector End Views
Chart for 2WD with A/T
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. Turn ON the ignition, with the engine OFF.
4. Select the “JR405E Automatic Transmission” in the system selection menu.
5. Monitor the Read Diagnostic Trouble Code (DTC) Info As Stored By ECU with the scan tool.
Does the transmission control module (TCM) DTC
P0722 set?
Go to Applicable
DTC in Automatic Transmission Section Go to Step 3
3 1. Drive the vehicle. 2. Select the data display function of engine control module (ECM).
3. Observe the Vehicle Speed parameter with the scan tool.
Does the Vehicle Speed parameter indicate correct
vehicle speed?
Go to Diagnostic Aids Go to Step 4
4 1. Turn OFF the ignition. 2. Disconnect the TCM harness connector.
3. Turn ON the ignition, with the engine OFF.
4. Intermittently jump the VSS signal output circuit (pin A-10 of C-94 connector) with a test lamp that
is connected to a known good ground while
monitoring the Vehicle Speed parameter with the
scan tool.
Does the scan tool indicate any vehicle speed when
the circuit is intermittently pulled to ground?
Go to Step 8 Go to Step 5
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ISUZU KB P190 2007

6E-210 Engine Control System (4JH1)
DTC P1520 (Symptom Code A) (Flash Code 47)
Circuit Description
(Manual Transmission)
The neutral switch is installed on the transmission gea
r
control box. W hen the gear position is neutral, the
switch is closed and the switch signal is provided to the
engine control module (ECM). If the ECM detects the
neutral switch signal is not changed from neutral during
the predetermined engine speed and vehicle speed
range, this DTC will set.
(Automatic Transmission)
The inhibitor switch is installed to the transmission case.
W hen the selector position is P or N range, the switch is
closed and the switch signal is provided to the Emir the
ECM detects the neutral switch signal is not changed
from P or N during the predetermined engine speed and
vehicle speed range, this DTC will set.
Condition for Running the DTC • 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).
Condition for Setting the DTC
• The ECM detects that the neutral switch signal is
continuously ON (neutral or P/N range) during
three consecutive driving cycles.
Action Taken When the DTC Sets
• The ECM illuminates the malfunction indicato
r
lamp (MIL) when the diagnostic runs and fails.
Condition for Clearing the MIL/DTC
Important: • Following conditions must be met two consecutive
driving cycles. (One driving cycle: Ignition switch
ON > Engine run > Vehicle run > Ignition switch
OFF for 10 seconds)
- 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)
- Other than neutral or P/N range
- After the above procedure is done, a history
DTC clears after 40 consecutive driving cycles
without a fault. Or clear with the scan tool.
Diagnostic Aids
• If an intermittent condition is suspected, refer to
Intermittent Conditions in this section.
DTC P1520 (Symptom Code A) (Flash Code 47)
Schematic Reference: Engine Controls Schematics
Connector End View Reference: Engine Controls
Connector End Views or Engine Control Module (ECM)
Connector End Views
Chart for M/T
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 ON the ignition, with the engine OFF.
3. Observe the Neutral Switch parameter with the scan tool while shift to neutral and other
positions.
Does the scan tool indicate ON when the position is
neutral and OFF when other than the neutral?
Go to Diagnostic Aids Go to Step 3
3 1. Turn OFF the ignition. 2. Disconnect the neutral switch harness connector.
3. Turn ON the ignition, with the engine OFF.
4. Observe the Neutral Switch parameter with the scan tool.
Does the scan tool indicate ON?
Go to Step 4 Go to Step 5
4 1. Test the neutral switch input signal circuit between the engine control module (ECM) (pin
87 of C-57 connector) and the neutral switch (pin
1 of E-11 connector) for a short to battery or
ignition voltage.
2. Repair the circuit(s) as necessary.
Did you find and correct the condition?
Go to Step 7 Go to Step 6
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ISUZU KB P190 2007

Engine Control System (4JH1) 6E-211
Step Action Value(s) Yes No
5 Replace the neutral switch. Refer to Neutral Switch
Replacement in Transmission Section.
Did you complete the replacement?
Go to Step 7
6 Important: Replacement ECM must be
programmed.
Replace the ECM. Refer to Engine Control Module
(ECM) Replacement in this section.
Did you complete the replacement?
Go to Step 7
7 1. Reconnect all previously disconnected harness
connector(s).
2. Clear the DTCs with the scan tool.
Important: Following conditions must be met two
consecutive driving cycles before clear with the scan
tool. (One driving cycle: Ignition switch ON > Engine
run > Vehicle run > Ignition switch OFF for 10
seconds) • The engine speed is higher than 1500 RPM
• The vehicle speed is higher than 63 km/h
(39 MPH)
• The clutch pedal is released
• Other than neutral
3. Turn ON the ignition, with the engine OFF.
4. Observe the Neutral Switch parameter with the scan tool while shift to neutral and other
positions.
Does the scan tool indicate ON when the position is
neutral and OFF when other than the neutral?
Go to Step 8 Go to Step 3
8 Observe the DTC Information with the scan tool. Are there any DTCs that you have not diagnosed? Go to Diagnostic
Trouble Code (DTC) List System OK
Chart for A/T
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. Turn ON the ignition, with the engine OFF.
4. Select the “JR405E Automatic Transmission” in the system selection menu.
5. Monitor the Read Diagnostic Trouble Code (DTC) Info As Stored By ECU with the scan tool.
Does the transmission control module (TCM) DTC
P0705 set?
Go to Applicable
DTC in Automatic Transmission Section Go to Step 3
3 1. Install the scan tool. 2. Turn ON the ignition, with the engine OFF.
3. Observe the Neutral Switch parameter with the scan tool while shift to P or N and other
positions.
Does the scan tool indicate ON when the position is
P or N and OFF when other than the P or N?
Go to Diagnostic Aids Go to Step 4
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ISUZU KB P190 2007