2007 ISUZU KB P190 Electrical

6E–112 ENGINE DRIVEABILITY AND EMISSIONS
22 1. Command the fuel pump ON with the Scan Tool.2. Using suitable pliers which will not damage thefuel hose, gradually apply pressure with the pliers
to pinch the flexible fuel return hose closed. 376 kPa
(55 psi)
Does the fuel pressure indicated by the fuel pressure
gauge rise above the first specified value?
Caution: Do not let the fuel pressure exceed the
second specified value. 414 kPa
(60 psi) Go to Step 11Go to Step 7
23 1. Command the fuel pump ON with the Scan Tool. 2. Remove the fuel filler cap and listen for the soundof the fuel pump running.
3. Turn the pump off.
Was the fuel pump running? — Go to Step 7Go to
Fuel
System
Electrical Test Chart
Step
Action Value(s) Yes No

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ISUZU KB P190 2007

6E–116 ENGINE DRIVEABILITY AND EMISSIONSP0135 A O
2 Sensor Heater Circuit (Bank 1 Sensor
1) 1. No DTC relating to MAP sensor and ECT
sensor.
2. Engine coolant temperature is more than 60 deg. C.
3. Engine run time is longer than 20 seconds.
4. MAP sensor output is more than 70kPa.
5. O
2 sensor bank 1 heater current more
than 10mA. No fail-safe function.
O
2 sensor bank 1 heater circuit is correct
condition. 1. Heater harness open, short to ground or
short to voltage circuit.
2. O
2 sensor heater malfunction.
3. ECM malfunction. J2-31
P0201 A Injector 1 Control Circuit 1. Engine is running. 2. Engine speed is more than 1000rpm.
3. Injector voltage does not meet to the battery voltage when the injector is
commanded Off or does not meet to the
0V when the injector is commanded On. Injector circuit is correct condition.
1. Injector harness open circuit, short to
ground or short to voltage circuit.
2. Injector malfunction.
3. ECM malfunction. J1-9
P0202 A Injector 2 Control Circuit J1-22
P0203 A Injector 3 Control Circuit J1-8
P0204 A Injector 4 Control Circuit J1-11
P0325 B Knock Sensor Module Circuit 1. No DTC relating to MAP sensor.
2. Engine coolant temperature is more than 50 deg. C.
3. Engine speed is more than 1600rpm.
4. Knock sensor filter module integrated circuit malfunction. ECM retards ignition timing 4 deg.
C . Knock sensor is correct condition.
1. KS harness open circuit.
2. Poor connector connection.
3. KS sensor malfunction.
4. ECM malfunction. J1-3/
J1-32
P0327 A Knock Sensor Circuit 1. No DTC relating to MAP sensor.
2. Engine coolant temperature is more than 50 deg. C.
3. Engine speed is more than 1600rpm.
4. Knock sensor harness short to ground or short to voltage circuit. 1. KS harness short to ground or short to
voltage circuit.
2. Poor connector connection.
3. KS sensor malfunction.
4. ECM malfunction. J1-3/
J1-32
P0336 B Crankshaft Position Sensor Circuit Range/ Performance (58X) 1. Engine is running.
2. Extra or missing pulse is detected consecutively. No fail-safe function.
Correct pulse is detected consecutively. 1. CKP sensor harness open circuit, short to
ground or short to voltage circuit.
2. Poor connector connection.
3. CKP sensor malfunction.
4. Pulse sensing gap incorrect.
5. Pluser malfunction.
6. Electrical interference.
7. Magnetic interference.
8. ECM malfunction. J1-6/
J1-21
P0337 B Crankshaft Position Sensor Circuit Low Input (58X) No pulse is detected during engine cranking.
1. CKP sensor harness open circuit, short to
ground or short to voltage.
2. Poor connector connection.
3. CKP sensor malfunction.
4. Pulse sensing gap incorrect.
5. Pluser malfunction.
6. Electrical interference.
7. Magnetic interference.
8. ECM malfunction. J1-6/
J1-21
Code Type
DTC Name DTC Setting Condition Fail-Safe (Back Up)Recovery Condition Related Failure PartsRelated
ECM
Pin No.

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ISUZU KB P190 2007

6E–118 ENGINE DRIVEABILITY AND EMISSIONSP1167 D Fuel Supply System Rich During
Deceleration Fuel Cutoff 1. No DTC relating to MAP sensor, TPS,
EVAP purge, ECT sensor, CKP sensor,
VSS, injector control circuit and ignition
control circuit.
2. O
2 sensor bank 1 output voltage is more
than 550mV in deceleration fuel cutoff
mode. No fail-safe function.
O
2 sensor output voltage is below 550mV. 1. Sensor harness open or short to ground
circuit.
2. O
2 sensor malfunction.
3. MAF sensor output is incorrect.
4. Air intake line malfunction.
5. IAC valve malfunction.
6. Low fuel pressure.
7. Injector malfunction.
8. EVAP purge solenoid valve malfunction.
9. Ignition system malfunction.
10. Spark plug malfunction. 11. ECM malfunction. J2-6/
J2-21
P1171 D Fuel Supply System Lean During Power Enrichment 1. No DTC relating to MAP sensor, TPS,
EVAP purge, ECT sensor, CKP sensor,
VSS, injector control circuit and ignition
control circuit.
2. Engine coolant temperature is more than 60deg. C.
3. Mass air flow is below 13.5m/s.
4. O
2 sensor bank 1 output voltage is below
350mV in power enrichment mode. No fail-safe function.
O
2 sensor output voltage is more than
350mV. 1. Sensor harness open or short to ground
circuit.
2. O
2 sensor malfunction.
3. MAF sensor output is incorrect.
4. Air intake line malfunction.
5. IAC valve malfunction.
6. Low fuel pressure.
7. Injector malfunction.
8. ECM malfunction. J2-6/
J2-21
P1625 B ECM System Reset ECM reset has occurred other than “On ”. Engine control disabled. Memory are is OK. 1. Electrical interference.
2. Magnetic interference.
3. ECM malfunction. -
P1626 - Immobilizer No Signal No response from immobilizer control unit. 1. Engine does not start.
2. Check engine lamp flash.No recovery.
1. ECM and immobilizer control unit
communication circuit open circuit, short to
ground circuit or short to voltage circuit.
2. ECM malfunction.
3. Immobilizer control unit malfunction.
4. Transponder key malfunction. J2-23/
J2-32
P1631 - Immobilizer Wrong Signal Received response is not correct. 1. ECM malfunction.
2. Immobilizer control unit malfunction.
3. Transponder key malfunction. -
P1648 - Wrong Security Code Entered Received incorrect security code. 1. ECM malfunction.
2. Immobilizer control unit malfunction.
3. Transponder key malfunction. -
P1649 - Immobilizer Function Not Programmed Immobilizer function is not programmed in the ECM. ECM malfunction.
-
P1693 B Tachometer Output Low Voltage Tacho output circuit short to ground circuit. No fail-safe function. Tacho output circuit is correct condition. 1. Tacho output circuit short to ground circuit.
2. Poor connector connection.
3. ECM malfunction. J2-25
Code Type
DTC Name DTC Setting Condition Fail-Safe (Back Up)Recovery Condition Related Failure PartsRelated
ECM
Pin No.

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ISUZU KB P190 2007

ENGINE DRIVEABILITY AND EMISSIONS 6E–203
2 1. Connect the Tech 2. 2. Review and record the failure information.
3. Select “F0: Read DTC Infor By Priority” in “F0: Diagnostic Trouble Code”.
Is the DTC P0562 stored as “Present Failure”? — Go to Step 3Refer to
Diagnostic Aids and Go to Step
3
3 1. Using the Tech2, ignition “On” and engine “Off”. 2. Select “Clear DTC Information” with the Tech2 andclear the DTC information.
3. Operate the vehicle and monitor the “F5: Failed This Ignition” in “F2: DTC Information”.
Was the DTC P0562 stored in this ignition cycle? — Go to Step 4Refer to
Diagnostic Aids and Go to Step
4
4 1. Using the Tech 2, ignition “On” and engine “On”. 2. Monitor the “Ignition Voltage” in the data display.
3. Load the electrical system by turning on the headlights, etc..
Does the Tech 2 indicate enough ignition voltage? 10 - 14.5V Go to Step 6Go to Step 5
5 Using the DVM and check the battery voltage at the battery terminal.
Does the tester indicate enough battery voltage?
10 - 14.5V Go to Step 6Check the
charging
system, charge or replace the battery
6 Check for poor/faulty connection at the ECM connector. If a poor/faulty connection is found, repair
as necessary.
Was the problem found?
— Verify repair Go to Step 7
7 Check for poor/faulty connection of the ECM ground at the inlet manifold. If a poor/faulty connection is
found, repair as necessary.
Was the problem found?
— Verify repair Go to Step 8
8 Is the ECM programmed with the latest software release?
If not, download the latest software to the ECM using
the “SPS (Service Programming System)”.
Was the problem solved? — Verify repair Go to Step 9
9 Replace the ECM. Is the action complete?
IMPORTANT: The replacement ECM must be
programmed. Refer to section of the Service
Programming System (SPS) in this manual.
Following ECM programming, the immobilizer system
(if equipped) must be linked to the ECM. Refer to
section 11 “Immobilizer System-ECM replacement” for
the ECM/Immobilizer linking procedure. — Verify repair —
Step
Action Value(s) Yes No
16
2
17
12
C-56(J2)
E-60(J1)
E-72

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ISUZU KB P190 2007

ENGINE DRIVEABILITY AND EMISSIONS 6E–205
2 1. Connect the Tech 2. 2. Review and record the failure information.
3. Select “F0: Read DTC Infor By Priority” in “F0: Diagnostic Trouble Code”.
Is the DTC P0563 stored as “Present Failure”? — Go to Step 3Refer to
Diagnostic Aids and Go to Step
3
3 1. Using the Tech2, ignition “On” and engine “Off”. 2. Select “Clear DTC Information” with the Tech2 andclear the DTC information.
3. Operate the vehicle and monitor the “F5: Failed This Ignition” in “F2: DTC Information”.
Was the DTC P0563 stored in this ignition cycle? — Go to Step 4Refer to
Diagnostic Aids and Go to Step
4
4 1. Using the Tech 2, ignition “On” and engine “On”. 2. Monitor the “Ignition Voltage” in the data display.
3. Load the electrical system by turning on the headlights, etc..
Does the Tech 2 indicate correct ignition voltage? Less than 16V Go to Step 5Check the
charging
system and Go to Step 5
5 Is the battery jamp start cable incorrectly connecting? —Ve r if y
procedure Go to Step 6
6 Is the ECM programmed with the latest software release?
If not, download the latest software to the ECM using
the “SPS (Service Programming System)”.
Was the problem solved? — Verify repair Go to Step 7
7 Replace the ECM. Is the action complete?
IMPORTANT: The replacement ECM must be
programmed. Refer to section of the Service
Programming System (SPS) in this manual.
Following ECM programming, the immobilizer system
(if equipped) must be linked to the ECM. Refer to
section 11 “Immobilizer System-ECM replacement” for
the ECM/Immobilizer linking procedure. — Verify repair —
Step
Action Value(s) Yes No

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6E–206 ENGINE DRIVEABILITY AND EMISSIONS
DIAGNOSTIC TROUBLE CODE (DTC) P0601 ECM MEMORY CHECKSUM
Condition for setting the DTC and action taken when the DTC sets
Circuit Description
The engine control module (ECM) used in this vehicle
utilizes an electrically erasable programmable read-only
memory (EEPROM). The EEPROM contains program
information and the calibrations required for engine,
transmission, and powertrain diagnostics operation.
Unlike the PROM used in past applications, the
EEPROM is not replaceable. When the ECM is
replaced or a calibration update is required, the ECM must be programmed using a Tech 2.Diagnostic Aids
• Diagnostic Trouble Code P0601 indicates that the
contents of the EEPROM have changed since the
ECM was programmed. The only possible repair is
ECM reprogramming or replacement. Check service
bulletins to program the replacement ECM with the
correct software and calibration for the vehicle.
Diagnostic Trouble Code (DTC) P0601 ECM Memory Checksum
Code Type DTC Name DTC Setting Condition Fail-Safe (Back Up)
P0601 A ECM Memory Checksum ECM memory area error.Engine control disabled.
StepAction Value(s) Yes No
1 Was the “On-Board Diagnostic (OBD) System Check” performed?
—Go to Step 2Go to
On Board
Diagnostic
(OBD) System Check
2 1. Connect the Tech 2. 2. Review and record the failure information.
3. Select “F0: Read DTC Infor By Priority” in “F0: Diagnostic Trouble Code”.
Is the DTC P0601 stored as “Present Failure”? — Go to Step 3Refer to
Diagnostic Aids and Go to Step
3
3 1. Using the Tech2, ignition “On” and engine “Off”. 2. Select “Clear DTC Information” with the Tech2 andclear the DTC information.
3. Operate the vehicle and monitor the “F5: Failed This Ignition” in “F2: DTC Information”.
Was the DTC P0601 stored in this ignition cycle? — Go to Step 4Refer to
Diagnostic Aids
4 Is the ECM programmed with the latest software release?
If not, download the latest software to the ECM using
the “SPS (Service Programming System)”.
Was the problem solved? — Verify repair Go to Step 5
5 Replace the ECM. Is the action complete?
IMPORTANT: The replacement ECM must be
programmed. Refer to section of the Service
Programming System (SPS) in this manual.
Following ECM programming, the immobilizer system
(if equipped) must be linked to the ECM. Refer to
section 11 “Immobilizer System-ECM replacement” for
the ECM/Immobilizer linking procedure. — Verify repair —

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ENGINE DRIVEABILITY AND EMISSIONS 6E–207
DIAGNOSTIC TROUBLE CODE (DTC) P0602 ECU PROGRAMMING ERROR
Condition for setting the DTC and action taken when the DTC sets
Circuit Description
The engine control module (ECM) used in this vehicle
utilizes an electrically erasable programmable read-only
memory (EEPROM). The EEPROM contains program
information and the calibrations required for engine,
transmission, and powertrain diagnostics operation.
Unlike the PROM used in past applications, the
EEPROM is not replaceable. When the ECM is replaced or a calibration update is required, the ECM
must be programmed using a Tech 2.
Diagnostic Aids
• Diagnostic Trouble Code P0602 indicates when non programmed ECM is used without service
programming system (SPS). The replacement ECM
must be programmed.
Diagnostic Trouble Code (DTC) P0602 ECU Programming Error
Code Type DTC Name DTC Setting Condition Fail-Safe (Back Up)
P0602 - ECU Programming Error ECM memory area error.Engine control disabled.
StepAction Value(s) Yes No
1 Was the “On-Board Diagnostic (OBD) System Check”
performed?
—Go to Step 2Go to
On Board
Diagnostic
(OBD) System Check
2 1. Connect the Tech 2.
2. Review and record the failure information.
3. Select “F0: Read DTC Infor By Priority” in “F0: Diagnostic Trouble Code”.
Is the DTC P0602 stored as “Present Failure”? — Go to Step 3Refer to
Diagnostic Aids
3 Download the latest software to the ECM using the
“SPS (Service Programming System)”.
Is the action complete? — Verify repair —

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6E–232 ENGINE DRIVEABILITY AND EMISSIONS
SYMPTOM DIAGNOSIS
PRELIMINARY CHECKS
Before using this section, perform the “On-Board
Diagnostic (OBD) System Check” and verify all of the
following items:
• The engine control module (ECM) and malfunction indicator lamp (MIL = Check Engine Lamp) are
operating correctly.
• There are no Diagnostic Trouble Code(s) stored.
• Tech 2 data is within normal operating range. Refer to Typical Scan Data Values.
• Verify the customer complaint and locate the correct symptom in the table of contents. Perform the
procedure included in the symptom chart.
VISUAL/PHYSICAL CHECK
Several of the symptom procedures call for a careful
visual/physical check. This can lead to correcting a
problem without further checks and can save valuable
time. This check should include the following items:
• ECM grounds for cleanliness, tightness and proper location.
• Vacuum hoses for splits, kinks, and proper connection, shown on the “Emission Control System
Schematics”. Check thoroughly for any type of leak or
restriction.
• Air intake ducts for collapsed or damaged areas.
• Air leaks at throttle body mounting area, manifold absolute pressure (MAP) sensor and intake manifold
sealing surfaces.
• Ignition wires for cracking, harness, and carbon tracking.
• Wiring for proper connections, pinches and cuts.
INTERMITTENT
Important: An intermittent problem may or may not turn
on the malfunction indicator lamp (MIL) or store a
Diagnostic Trouble Code. Do NOT use the Diagnostic
Trouble Code (DTC) charts for intermittent problems.
The fault must be present to locate the problem.
Most intermittent problems are cased by faulty electrical
connections or wiring. Perform a careful visual/physical
check for the following conditions.
• Poor mating of the connector halves or a terminal not fully seated in the connector (backed out).
• Improperly formed or damaged terminal.
• All connector terminals in the problem circuit should be carefully checked for proper contact tension.
• Poor terminal-to-wire connection. This requires removing the terminal form the connector body to
check.
• Ignition coils shorted to ground and arcing at ignition wires or plugs. • MIL (Check Engine Lamp) wire to ECM shorted to
ground.
• Poor ECM grounds. Refer to the ECM wiring diagrams.
Road test the vehicle with a Digital Multimeter
connected to a suspected circuit. An abnormal voltage
when the malfunction occurs is a good indication that
there is a fault in the circuit being monitored.
Using Tech 2 to help detect intermittent conditions. The
Tech 2 has several features that can be used to located
an intermittent condition.
An intermittent MIL (Check Engine Lamp) with no stored
Diagnostic Trouble Code may be caused by the
following:
• Ignition coil shorted to ground and arcing at ignition wires or plugs.
• MIL (Check Engine Lamp) wire to ECM short to ground.
• Poor ECM grounds. Refer to the ECM wiring diagrams.
Check for improper installation of electrical options such
as light, cellular phones, etc. Check all wires from ECM
to the ignition control module for poor connections.
Check for an open diode across the A/C compressor
clutch and check for other open diodes (refer to wiring
diagrams in Electrical Diagnosis).
If problem has not been found, refer to ECM connector
symptom tables.
• Check the “Broadcast Code” of the ECM, and compare it with the latest Isuzu service bulletins and/
or Isuzu EEPROM reprogramming equipment to
determine if an update to the ECM’s reprogrammable
memory has been released.
To check the “Broadcast Code”, connect the Tech 2,
then look for “ID info.” then select “Broadcast Code”.
This should display a 4 character code, such as “XBYA”
(example only).
This identifies the contents of the reprogrammable
software and calibration contained in the ECM.
If the “Broadcast Code” is not the most current
available, it is advisable to reprogram the ECM’s
EEPROM memory, which may either help identify a
hard-to find problem or may fix the problem.
The Service Programming System (SPS) will not allow
incorrect software programming or incorrect calibration
changes.

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