2004 ISUZU TF SERIES engine

6E–198 ENGINE DRIVEABILITY AND EMISSIONS
9 Using the DVM and check the VSS ground circuit.
1. Ignition “On”, engine “Off”.
2. Disconnect the VSS connector.
3. Check the circuit for short to power supply circuit.
Was the DVM indicated specified value?
Less than 1V Go to Step 10Repair faulty
harness and
verify repair
10 Using the DVM and check the VSS ground circuit.
1. Ignition “Off”, engine “Off”.
2. Disconnect the VSS connector.
3. Check the circuit for open circuit.
Was the problem found?
—Repair faulty
harness and
verify repair Go to Step 19
11 Using the DVM and check the VSS signal circuit.
1. Ignition “On”, engine “Off”.
2. Disconnect the VSS connector and meter
connector.
3. Check the circuit for short to power supply circuit.
Was the DVM indicated specified value?
Less than 1V Go to Step 12Repair faulty
harness and
verify repair Step A ction Value(s) Yes No
V
E-44
2
E-44
2
V
B-24
9

ENGINE DRIVEABILITY AND EMISSIONS 6E–199
12 Using the DVM and check the VSS signal circuit.
1. Ignition “Off”, engine “Off”.
2. Disconnect the VSS connector and meter
connector.
3. Check the circuit for open or short to ground
circuit.
If a open or short to ground circuit is found, repair the
faulty harness and verify repair.
Is the action complete?
—Veri fy repai r—
13 Replace the speed meter.
Is the action complete?—Veri fy repai r—
14 Using the DVM and check the VSS signal circuit.
1. Ignition “On”, engine “Off”.
2. Disconnect the meter connector and immobilizer
control unit connector (if equipped).
3. Check the circuit for short to power supply circuit.
Was the DVM indicated specified value?
Less than 1V Go to Step 15Repair faulty
harness and
verify repair
15 Using the DVM and check the VSS signal circuit.
1. Ignition “Off”, engine “Off”.
2. Disconnect the meter connector and immobilizer
control unit connector (if equipped).
3. Check the circuit for open or short to ground
circuit.
If a open or short to ground circuit is found, repair the
faulty harness and verify repair.
Is the action complete?
—Veri fy repai r— Step A ction Value(s) Yes No
B-24
9E-44
3
V
B-68
6
B-24
10B-68
6

6E–200 ENGINE DRIVEABILITY AND EMISSIONS
16 Replace the immobilizer control unit (if equipped).
Is the action complete?—Veri fy repai r—
17 Using the DVM and check the VSS signal circuit.
1. Ignition “Off”, engine “Off”.
2. Disconnect the immobilizer control unit connector
(if equipped) and ECM connector.
3. Ignition “On”.
4. Check the circuit for short to power supply circuit.
Was the DVM indicated specified value?
Less than 1V Go to Step 18Repair faulty
harness and
verify repair
18 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
(if equipped).
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
(if equipped) 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 Step 21
19 Substitute a known good VSS and recheck.
Was the problem solved?—Go to Step 20Go to Step 21 Step A ction Value(s) Yes No
V
C-56(J2)
23
J2-32Breaker BoxB-68




B-68 C-56(J2)
23
8

ENGINE DRIVEABILITY AND EMISSIONS 6E–201
20 Replace the VSS.
Was the problem solved?—Verify repair Go to Step 21
21 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 22
22 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.—Veri fy repai r— Step A ction Value(s) Yes No

6E–202 ENGINE DRIVEABILITY AND EMISSIONS
DIAGNOSTIC TROUBLE CODE (DTC) P0562 SYSTEM VOLTAGE LOW
Condition for setting the DTC and action taken when the DTC sets
Circuit Description
The engine control module (ECM) monitors the system
voltage on the ignition feed terminal to the ECM. A
system voltage Diagnostic Trouble Code will set
whenever the voltage is below a calibrated value.
Diagnostic Aids
If the Diagnostic Trouble Code sets when an
accessory is operated, check for a poor connection or
excessive current draw.
Check for open circuits or shorts to ground on the
ECM’s battery or ignition inputs.
Diagnostic Trouble Code (DTC) P0562 System Voltage Low
Code Type DTC Name DTC Setting Condition Fail-Safe (Back Up)
P0562 D System Voltage Low Battery voltage is below 11V. No fail-safe function.
Step A ction 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

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 and
clear 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.—Veri fy repai r— Step A ction Value(s) Yes No
16
2
17
12 C-56(J2)E-60(J1)
E-72

6E–204 ENGINE DRIVEABILITY AND EMISSIONS
DIAGNOSTIC TROUBLE CODE (DTC) P0563 SYSTEM VOLTAGE HIGH
Condition for setting the DTC and action taken when the DTC sets
Circuit Description
The engine control module (ECM) monitors the system
voltage on the ignition feed terminals to the ECM. A
system voltage Diagnostic Trouble Code will setwhenever the voltage is above a calibrated value.Diagnostic Aids
Check for a faulty charging system components.
Diagnostic Trouble Code (DTC) P0563 Sy stem Voltage High
Code Type DTC Name DTC Setting Condition Fail-Safe (Back Up)
P0563 A System Voltage High Battery voltage is above 16V. No fail-safe function.
Step A ction 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

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 and
clear 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?
—Verify
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.—Veri fy repai r— Step A ction Value(s) Yes No