Page 2336 of 6020

6E–166 ENGINE DRIVEABILITY AND EMISSIONS
10 Using the DVM and check the heater ground circuit.1. Ignition “On”, engine “Off”.
2. Disconnect the O
2 sensor connector.
3. Check the circuit for short to voltage circuit.
Was the DVM indicated voltage?
—Repair faulty
harness and verify repair Go to Step 12
11 Replace the O
2 sensor.
Was the problem solved? — Verify repair Go to Step 12
12 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 13
13 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
3
V
E77
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ISUZU KB P190 2007
Page 2343 of 6020

ENGINE DRIVEABILITY AND EMISSIONS 6E–173
10 Using the DVM and check the injector signal circuit.1. Ignition “On”, engine “Off”.
2. Disconnect the injector connector for the affected cylinder.
3. Check the circuit for short to voltage circuit.
Was the DVM indicated voltage?
—Repair faulty
harness and verify repair Go to Step 12
11 Replace the injector for the affected cylinder. Was the problem solved? — Verify repair Go to Step 12
12 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 13
13 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
V
2
E-6
No.1 Cylinder
V
2
E-7
No.2 Cylinder
V
2
E-8
No.3 Cylinder
V
2
E-9
No.4 Cylinder
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Page 2346 of 6020

6E–176 ENGINE DRIVEABILITY AND EMISSIONS
8 Using the DVM and check the knock sensor 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 knock sensor.
4. Check the circuit for open circuit.
Was the problem found?
Breaker box is not available: 1. Ignition “Off”, engine “Off”.
2. Disconnect the knock sensor connector and ECM connector.
3. Check the circuit for open circuit.
Was the problem found?
—Repair faulty
harness and verify repair Go to Step 9
9 Substitute a known good knock sensor and recheck. Was the problem solved? — Go to Step 10 Go to Step 11
10 Replace the knock sensor. Was the problem solved? — Verify repair Go to Step 11
11 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 12
12 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
J1-3J1-32
Breaker Box
E-8421
Ω
Ω
3
E-60(J1)
E-84
322
1
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ISUZU KB P190 2007
Page 2349 of 6020

ENGINE DRIVEABILITY AND EMISSIONS 6E–179
7 Using the DVM and check the knock sensor circuit.1. Ignition “On”, engine “Off”.
2. Disconnect the knock sensor connector.
3. Check the circuit for short to voltage circuit.
Was the DVM indicated voltage?
—Repair faulty
harness and verify repair Go to Step 8
8 Substitute a known good knock sensor and recheck. Was the problem solved? — Go to Step 9Go to Step 10
9 Replace the knock sensor. Was the problem solved? — Verify repair Go to Step 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
VV
E-84
2
1
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ISUZU KB P190 2007
Page 2355 of 6020

ENGINE DRIVEABILITY AND EMISSIONS 6E–185
13 Check any accessory parts which may cause electricinterference or magnetic interference.
Was the problem found? —Remove the
accessory parts
and verify repair Go to Step 14
14 Substitute a known good CKP sensor and recheck. Was the problem solved? — Go to Step 15Go to Step 16
15 Replace the CKP sensor. Was the problem solved? — Verify repair Go to Step 16
16 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 17
17 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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ISUZU KB P190 2007
Page 2360 of 6020

6E–190 ENGINE DRIVEABILITY AND EMISSIONS
8 Using the DVM and check the ignition coil modulepower supply circuit.
1. Ignition “On”, engine “Off”.
2. Disconnect the ignition coil module connector.
3. Check the circuit for open circuit.
Was the DVM indicated specified value?
10 - 14.5V Go to Step 10Go to Step 9
9 Repair the open or short to ground circuit between the “IGN. Coil” fuse (15A) and ignition coil module.
Is the action complete? — Verify repair —
10 Replace the ignition coil module. Was the problem solved? — Verify repair Go to Step 11
11 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 12
12 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
V
E-18
2
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ISUZU KB P190 2007
Page 2364 of 6020

6E–194 ENGINE DRIVEABILITY AND EMISSIONS
9 Using the DVM and check the purge solenoid valvesignal circuit.
1. Ignition “On”, engine “Off”.
2. Disconnect the purge solenoid valve connector.
3. Check the circuit for short to voltage circuit.
Was the DVM indicated voltage?
—Repair faulty
harness and verify repair Go to Step 10
10 Substitute a known good purge solenoid valve and recheck.
Was the problem solved? — Go to Step 11Go to Step 12
11 Replace the purge solenoid valve. Was the problem solved? — Verify repair Go to Step 12
12 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 13
13 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
V
E-66
1
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ISUZU KB P190 2007
Page 2366 of 6020

6E–196 ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0502 Vehicle Speed Sensor Circuit Low Input
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 P0502 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 P0502 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 VSS, meter, immobilizer control unit (if equipped), ECM and other
connectors. If a poor/faulty connection is found, repair
the faulty terminal.
Was the problem found?
— Verify repair Go to Step 5
5 Remove the VSS from the housing case and visually check.
Was the problem found? — Go to Step 19Go to Step 6
6 8
23
27
910
C-56(J2)
B-68
B-24
E-44
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ISUZU KB P190 2007