ISUZU KB P190 2007 Workshop Repair Manual

ENGINE DRIVEABILITY AND EMISSIONS 6E–221
9 Using the DVM and check the VSS signal circuit.Breaker box is available:
1. Ignition “Off”, engine “Off”.
2. Install the breaker box as type A. (ECM disconnected) Refer to 6E-88 page.
3. Disconnect the immobilizer control unit connector.
4. Check the circuit for open or shot to ground circuit.
Was the problem found?
Breaker box is not available: 1. Ignition “Off”, engine “Off”.
2. Disconnect the immobilizer control unit connector and ECM connector.
3. Check the circuit for open or short to ground circuit.
Was the problem found?
—Repair faulty
harness and verify repair Go to Srtep 10
10 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 11
11 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
J2-23Breaker BoxB-688
ΩΩ
23B-68
C-56(J2)
8

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

6E–222 ENGINE DRIVEABILITY AND EMISSIONS
DIAGNOSTIC TROUBLE CODE (DTC) P1631 IMMOBILIZER WRONG SIGNAL
Condition for setting the DTC and action taken when the DTC sets
Circuit Description
The ECM decides whether that is an abnomality in the
immobilizer control system. DTC P1631 is recorded by
the ECM when received response was not correct.
Diagnostic Aids
Check for the following conditions:
• Poor connection at ECM and Immobilizer-Inspect harness connectors for backed out terminals,
improper mating, broken locks, improperly formed or damaged terminals, and poor terminal to wire
connection.
• Damaged harness-Inspect the wiring harness for damage, If the harness appears to be OK, disconnect
the ECM and Immobilizer, turn the ignition “ON” and
observe a voltmeter connected to the suspect driver
circuit at the ECM and Immobilizer harnass connector
while moving connectors and wiring harnesses
relates to the MIL. A change in voltage will indicate
the location of the fault.
Code Type DTC Name DTC Setting Condition Fail-Safe (Back Up)
P1631 - Immobilizer Wrong Signal Received response is not correct.1. Engine does not start.
2. Check engine lamp flash.

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

ENGINE DRIVEABILITY AND EMISSIONS 6E–223
Diagnostic Trouble Code (DTC) P1631 Immobilizer Wrong Signal
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 P1631 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 P1631 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 “Off”. 2. Select “Immobilizer” in the system selection menu“Body”.
3. Select “Read DTC Info Ordered By Priority” in the “Diagnositic Trouble Code”.
Was the DTC B0007 stored in this ignition cycle? —Refer to
“Immobilizer Workshop
Manual” & Go to DTC Chart B0007 Go to Step 5
5 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 6
6 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 —

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

6E–224 ENGINE DRIVEABILITY AND EMISSIONS
DIAGNOSTIC TROUBLE CODE (DTC) P1648 WRONG SECURITY CODE ENTERED
Condition for setting the DTC and action taken when the DTC sets
Circuit Description
The ECM decides whether that is an abnomality in the
immobilizer control system. DTC P1648 is recorded by
the ECM when received incorrect security code.
Diagnostic Aids
Check for the following conditions:
• Poor connection at ECM and Immobilizer-Inspect harness connectors for backed out terminals,
improper mating, broken locks, improperly formed or damaged terminals, and poor terminal to wire
connection.
• Damaged harness Inspect the wiring harness for damage, If the harness appears to be OK, disconnect
the ECM and Immobilizer, turn the ignition “ON” and
observe a voltmeter connected to the suspect driver
circuit at the ECM and Immobilizer harnass connector
while moving connectors and wiring harnesses
relates to the MIL. A change in voltage will indicate
the location of the fault.
Code Type DTC Name DTC Setting Condition Fail-Safe (Back Up)
P1648 - Wrong Security Code Entered Received incorrect security code. 1. Engine does not start.
2. Check engine lamp flash.

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

ENGINE DRIVEABILITY AND EMISSIONS 6E–225
Diagnostic Trouble Code (DTC) P1648 Wrong Security Code Entered
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 P1648 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 P1648 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 “Off”. 2. Select “Immobilizer” in the system selection menu“Body”.
3. Select “Read DTC Info Ordered By Priority” in the “Diagnositic Trouble Code”.
Was the DTC B0007 stored in this ignition cycle? —Refer to
“Immobilizer Workshop
Manual” & Go to DTC Chart B0007 Go to Step 5
5 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 6
6 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 —

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

6E–226 ENGINE DRIVEABILITY AND EMISSIONS
DIAGNOSTIC TROUBLE CODE (DTC) P1649
IMMOBILIZER FUNCTION NOT PROGRAMMED
Condition for setting the DTC and action taken when the DTC sets
Circuit Description
The ECM decides whether that is an abnomality in the
immobilizer control system. DTC P1649 is recorded by
the ECM when security code & secret key not
programmed.
Diagnostic Aids
Check for the following conditions:
• Poor connection at ECM and Immobilizer-Inspect harness connectors for backed out terminals, improper mating, broken locks, improperly formed or
damaged terminals, and poor terminal to wire
connection.
• Damaged harness Inspect the wiring harness for damage, If the harness appears to be OK, disconnect
the ECM and Immobilizer, turn the ignition “ON” and
observe a voltmeter connected to the suspect driver
circuit at the ECM and Immobilizer harnass connector
while moving connectors and wiring harnesses
relates to the MIL. A change in voltage will indicate
the location of the fault.
Code Type DTC Name DTC Setting Condition Fail-Safe (Back Up)
P1649 - Immobilizer Function Not Programmed Immobilizer function is not programmed in the ECM.1. Engine does not start.
2. Check engine lamp flash.

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

ENGINE DRIVEABILITY AND EMISSIONS 6E–227
Diagnostic Trouble Code (DTC) P1649 Immobilizer Function Not Programmed
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 P1649 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 P1649 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 “Off”. 2. Select “Immobilizer” in the system selection menu“Body”.
3. Select “Read DTC Info Ordered By Priority” in the “Diagnositic Trouble Code”.
Were the any DTC's B0002 or B0009 stored in this
ignition cycle? —Refer to
“Immobilizer Workshop
Manual” & Go to DTC Chart B0002 or B0009 Go to Step 5
5 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 6
6 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 —

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

6E–228 ENGINE DRIVEABILITY AND EMISSIONS
DIAGNOSTIC TROUBLE CODE (DTC) P1693 TACHOMETER OUTPUT LOW VOLTAGE
Condition for setting the DTC and action taken when the DTC sets
Circuit Description
Based on the information from the Crank Position
Sensor (CKP), X58 reference signal is generated at
each rotation of the crankshaft.
Engine Control Module (ECM) converts X58 reference
signal into the square wave signal which is used to drive
the pulse generator of the tachometer.
When the wave length of the output signal is long, the
tacho meter indicates the engine speed is low, and vise
versa.
This malfunction detects a low impedance short to ground or open contact on the Tacho output, the
Diagnostic Trouble Code P1693 will be set.
Diagnostic Aids
• Poor connections or a damaged harness - Inspect the harness connections for: backed out terminals,
imprope, mating or damaged terminals. Also check
for open circuit, short to ground, and short to voltage.
• This malfunction detects a low impedance short to ground or open contact on the ECM out put circuit.
Code Type DTC Name DTC Setting Condition Fail-Safe (Back Up)
P1693 B Tachometer Output Low Voltage Tacho output circuit short to ground circuit. No fail-safe function.

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

ENGINE DRIVEABILITY AND EMISSIONS 6E–229
Diagnostic Trouble Code (DTC) P1693 Tachometer Output Low Voltage
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 P1693 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 P1693 stored in this ignition cycle? — Go to Step 4Refer to
Diagnostic Aids and Go to Step
4
4 Check for poor/faulty connection at the ECM or meter connector. If a poor/faulty connection is found, repair
the faulty terminal.
Was the problem found?
— Verify repair Go to Step 5
5 If a oscilloscope is available, monitor the Tachometer output signal. Does the oscilloscope indicate correct
wave form?
—Go to Step 10Not available:
Go to Step 6
Fixed at low: Go to Step 6
Fixed at High: Go to Step 7
25
C-56(J2) B-24
11
Crankshaft Position (CKP) Sensor & Tacho Output Signal
Reference Wave Form





CH1
0V





CH2
0V




Measurement Terminal: CH1: J1-21(+) / CH2: J2-25(+) GND(-)
Measurem ent Scale: CH1: 2V/div / CH2: 10V/div 5m s/div
Measurement Condition: Approxim ately 2000rpm

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

6E–230 ENGINE DRIVEABILITY AND EMISSIONS
6 Using the DVM and check the Tacho output circuit. Breaker box is available:
1. Ignition “Off”, engine “Off”.
2. Install the breaker box as type A. (ECM disconnected) Refer to 6E-88 page.
3. Disconnect the meter connector.
4. Check the circuit for open or short to ground circuit.
Was the problem found?
Breaker box is not available: 1. Ignition “Off”, engine “Off”.
2. Disconnect the ECM connector.
3. Disconnect the meter connector.
4. Check the circuit for open or short to ground circuit.
Was the problem found?
—Repair faulty
harness and verify repair Go to Step 7
7 Using the DVM and check the Tacho output circuit. 1. Ignition “On”, engine “Off”.
2. Disconnect the meter connector.
3. Check the circuit for short to power supply circuit.
Was the DVM indicated specified value?
Less than 1V Go to Step 8Repair faulty
harness and verify repair
8 Check any accessory parts which may cause electric interference or magnetic interference.
Was the problem found? —Remove the
accessory parts
and verify repair Go to Step 9
Step
Action Value(s) Yes No
J2-25
Breaker BoxB-2411
ΩΩ
1125C-56(J2)B-24
V
B-24
11

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007