ignition ISUZU TF SERIES 2004 Workshop Manual

6E–128 ENGINE DRIVEABILITY AND EMISSIONS
circuit. If the harness appears to be OK, observe the
IAT display on the Tech 2 while moving connectors
and wiring harnesses related to the IAT sensor. Achange in the IAT display will indicate the location of
the fault.
Diagnostic Trouble Code (DTC) P0112
Intake Air Temperature Sensor Low Input
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
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 P0112 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 P0112 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 IAT sensor or
ECM connector. If a poor/faulty connection is found,
repair as necessary.
Was the problem found?
—Verify repair Go to Step 5
5 Remove the IAT sensor and visually check.
Was the problem found? —Go to Step 8Go to Step 6
C56(J2) C121
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ENGINE DRIVEABILITY AND EMISSIONS 6E–129
6 Using the DVM and check the IAT sensor.
1. Ignition “Off”, engine “Off”.
2. Disconnect IAT sensor connector.
3. Measure the resistance of IAT sensor.
Does the tester indicate standard resistance as shown
in the following table?
Standard
resistance Go to Step 7Go to Step 8
7 Using the DVM and check the IAT sensor 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 IAT sensor connector.
4. Check the circuit for short to sensor ground or
ground circuit.
Was the problem found?
Breaker box is not available:
1. Ignition “Off”, engine “Off”.
2. Disconnect the IAT sensor connector.
3. Check the circuit for short to sensor ground or
ground circuit.
Was the problem found?
—Repair faulty
harness and
verify repair Go to Step 10 Step A ction Value(s) Yes No
Tempe rature (°C) Resistance (
) (Approx ima tely)
-20 32500
0 9910
20 3400
40 1509
60 670
80 329
100 182
120 101


IAT Sensor



J2 -1J2-22 Breaker Box




C56(J2)
122

6E–132 ENGINE DRIVEABILITY AND EMISSIONS
terminals, and poor terminal-to-wire connection.
Damaged harness - Inspect the wiring harness for
damage, short to ground, short to battery positive,
and open circuit. If the harness appears to be OK,observe the IAT display on the Tech 2 while moving
connectors and wiring harnesses related to the IAT
sensor. A change in the IAT display will indicate the
location of the fault.
Diagnostic Trouble Code (DTC) P0113
Intake Air Temperature Sensor High Input
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
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 P0113 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 P0113 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 IAT sensor or
ECM connector. If a poor/faulty connection is found,
repair as necessary.
Was the problem found?
—Verify repair Go to Step 5
5 Visually check the IAT sensor.
Was the problem found? —Go to Step 12Go to Step 6
C56(J2) C121
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ENGINE DRIVEABILITY AND EMISSIONS 6E–133
6 Using the DVM and check the IAT sensor.
1. Ignition “Off”, engine “Off”.
2. Disconnect IAT sensor connector.
3. Measure the resistance of IAT sensor.
Does the tester indicate standard resistance as shown
in the following table?
Standard
resistance Go to Step 7Go to Step 12
7 Using the DVM and check the IAT sensor signal
circuit.
1. Ignition “On”, engine “Off”.
2. Disconnect the IAT sensor connector.
3. Check the circuit for open circuit.
Was the DVM indicated specified value?
Approx imately
5.0V Go to Step 10Less than 1V:
Go to Step 8
More than
specified value:
Go to Step 9
8 Repair the open circuit between the ECM and IAT
sensor.
Was the problem solved?
—Verify repair Go to Step 14
9 Repair the short to voltage circuit between the ECM
and IAT sensor.
Was the problem solved?
—Verify repair Go to Step 14 Step A ction Value(s) Yes No
Temperature (°C) Resistance (
) (Approx ima tely)
-20 32500
0 9910
20 3400
40 1509
60 670
80 329
100 182
120 101


IAT Sensor



V
C121
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C56(J2) C121
122
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6E–134 ENGINE DRIVEABILITY AND EMISSIONS
10 Using the DVM and check the IAT sensor ground
circuit.
1. Ignition “On”, engine “Off”.
2. Disconnect the IAT sensor connector.
3. Check the circuit for short to power supply circuit.
Was the DVM indicated specified value?
Less than 1V Go to Step 11Repair faulty
harness and
verify repair
11 Using the DVM and check the IAT sensor ground
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 IAT sensor connector.
4. Check the circuit for open circuit.
Was the problem found?
Breaker box is not available:
1. Ignition “Off”, engine “Off”.
2. Disconnect the IAT sensor connector.
3. Check the circuit for open circuit.
Was the problem found?
—Repair faulty
harness and
verify repair Go to Step 14
12 Substitute a known good IAT sensor assembly and
recheck.
Was the problem solved?—Go to Step 13Go to Step 14
13 Replace the IAT sensor assembly.
Is the action complete?—Veri fy repai r—
14 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 15 Step A ction Value(s) Yes No
V
C121
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J2- 1Breaker BoxC-121



C56(J2) C121
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ENGINE DRIVEABILITY AND EMISSIONS 6E–137
Diagnostic Trouble Code (DTC) P0117
Engine Coolant Temperature Sensor Low Input
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
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 P0117 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 P0117 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 ECT sensor or
ECM connector. If a poor/faulty connection is found,
repair as necessary.
Was the problem found?
—Verify repair Go to Step 5
5 Visually check the ECT sensor.
Was the problem found? —Go to Step 8Go to Step 6
6 Using the DVM and check the ECT sensor.
1. Ignition “Off”, engine “Off”.
2. Disconnect ECT sensor connector.
3. Measure the resistance of ECT sensor.
Does the tester indicate standard resistance as shown
in the following table?
Standard
resistance Go to Step 7Go to Step 8
E60(J1) E69
32 27
Temperature (°C) Resistance (
) (Approx ima tely)
-20 26740
0 9120
20 3500
40 1464
60 664
80 333
100 175
120 102


ECT Sensor




6E–138 ENGINE DRIVEABILITY AND EMISSIONS
7 Using the DVM and check the ECT sensor 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 ECT sensor connector.
4. Check the circuit for short to sensor ground or
ground circuit.
Was the problem found?
Breaker box is not available:
1. Ignition “Off”, engine “Off”.
2. Disconnect the ECT sensor connector.
3. Check the circuit for short to sensor ground or
ground circuit.
Was the problem found?
—Repair faulty
harness and
verify repair Go to Step 10
8 Substitute a known good ECT sensor assembly and
recheck.
Was the problem solved?—Go to Step 9Go to Step 10
9 Replace the ECT sensor.
Is the action complete?—Veri fy repai r—
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
11Replace 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
J1-27J1-32


Breaker Box


E60(J1)
2732

6E–140 ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0118
Engine Coolant Temperature Sensor High Input
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
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 P0118 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 P0118 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 ECT sensor or
ECM connector. If a poor/faulty connection is found,
repair as necessary.
Was the problem found?
—Verify repair Go to Step 5
5 Visually check the ECT sensor.
Was the problem found? —Go to Step 12Go to Step 6
6 Using the DVM and check the ECT sensor.
1. Ignition “Off”, engine “Off”.
2. Disconnect ECT sensor connector.
3. Measure the resistance of ECT sensor.
Does the tester indicate standard resistance as shown
in the following table?
Standard
resistance Go to Step 7Go to Step 12
E60(J1) E69
32 27
Temperature (°C) Resistance (
) (Approx ima tely)
-20 26740
0 9120
20 3500
40 1464
60 664
80 333
100 175
120 102


ECT Sensor




ENGINE DRIVEABILITY AND EMISSIONS 6E–141
7 Using the DVM and check the ECT sensor signal
circuit.
1. Ignition “On”, engine “Off”.
2. Disconnect the ECT sensor connector.
3. Check the circuit for open circuit.
Was the DVM indicated specified value?
Approx imately
5.0V Go to Step 10Less than 1V:
G o t o S t e p 8
More than
specified value:
Go to Step 9
8 Repair the open circuit between the ECM and ECT
sensor.
Was the problem solved?
—Verify repair Go to Step 14
9 Repair the short to voltage circuit between the ECM
and ECT sensor.
Was the problem solved?
—Verify repair Go to Step 14
10 Using the DVM and check the ECT sensor ground
circuit.
1. Ignition “On”, engine “Off”.
2. Disconnect the ECT sensor connector.
3. Check the circuit for short to power supply circuit.
Was the DVM indicated specified value?
Less than 1V Go to Step 11Repair faulty
harness and
verify repair Step A ction Value(s) Yes No
V
E69
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E60(J1) E69
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E60(J1) E69
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E69
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6E–142 ENGINE DRIVEABILITY AND EMISSIONS
11 Using the DVM and check the ECT sensor ground
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 ECT sensor connector.
4. Check the circuit for open circuit.
Was the problem found?
Breaker box is not available:
1. Ignition “Off”, engine “Off”.
2. Disconnect the ECT sensor connector.
3. Check the circuit for open circuit.
Was the problem found?
—Repair faulty
harness and
verify repair Go to Step 14
12 Substitute a known good ECT sensor assembly and
recheck.
Was the problem solved?—Go to Step 13Go to Step 14
13 Replace the ECT sensor.
Is the action complete?—Veri fy repai r—
14 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 15
15 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
J1-32Breaker Box


E-69

232E60(J1) E69