ignition ISUZU TF SERIES 2004 Workshop Manual
Page 2152 of 4264
6E-156 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Step Action Value (s) Yes No
5
Remove the MAF & IAT sensor assembly and visually
check.
Was the problem found?
- Go to Step 9 Go to Step 6
6
Using the DVM and check the MAF 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-95 page.
3. Disconnect the MAF sensor connector.
4. Check the circuit for open circuit.
Was the problem found?
B39
Breaker BoxE-63
Breaker box is not available:
1. Ignition "Off", engine "Off".
2. Disconnect the MAF sensor connector and ECM
connector.
3. Check the circuit for open circuit.
Was the problem found?
E-63 E-61(B)
-
Repair faulty
harness and
verify repair
Go to Step 7
Page 2153 of 4264
3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-157
Step Action Value (s) Yes No
7
Using the DVM and check the MAF sensor ground
circuit.
1. Ignition "On", engine "Off".
2. Disconnect the MAF sensor connector .
3. Check the circuit for short to power supply circuit.
Was the DVM indicated specified value?
E-63
V
Less than 1V
Go to Step 8
Repair faulty
harness and
verify repair
8
Using the DVM and check the MAF sensor signal
circuit.
1. Ignition "On", engine "Off".
2. Disconnect the MAF sensor connector.
3. Check the circuit for short to power supply circuit.
Was the DVM indicated specified value?
E-63
V
Less than 1V
Go to Step 11
Repair faulty
harness and
verify repair
9
Substitute a known good MAF & IAT sensor assembly
and recheck.
Was the problem solved?
- Go to Step 10 Go to Step 11
10
Replace the MAF & IAT sensor assembly.
Is the action complete?
- Verify repair -
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 -
Page 2155 of 4264
3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-159
Diagnostic Trouble Code (DTC) P0112 (Flash Code 23) Intake Air Temperature
(IAT) Sensor Low Input
Step Action Value (s) Yes No
1
Was the "On-Board Diagnostic (OBD) System Check"
performed?
- Go to Step 2 Go 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 3 Refer 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 4 Refer 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?
E-60(A)
E-61(B)
E-63
- Verify repair Go to Step 5
5
Remove the MAF & IAT sensor assembly and visually
check.
Was the problem found?
- Go to Step 8 Go to Step 6
Page 2156 of 4264
6E-160 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Step Action Value (s) Yes No
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?
MAF & IAT Sensor
Temperature (C) Resistance ()
(Approximately)
-20 15230
0 5760
20 2480
40 1185
60 584
80 332
100 183
120 11 9Standard
resistance Go to Step 7 Go to Step 8
Page 2157 of 4264
3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-161
Step Action Value (s) Yes No
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-95 page.
3. Disconnect the IAT sensor connector.
4. Check the circuit for short to sensor ground or
ground circuit.
Was the problem found?
A19B39
Breaker Box
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?
E-60(A)
E-61(B)
-
Repair faulty
harness and
verify repair
Go to Step 10
8
Substitute a known good MAF & IAT sensor assembly
and recheck.
Was the problem solved?
- Go to Step 9 Go to Step 10
9
Replace the MAF & IAT sensor assembly.
Is the action complete?
- Verify repair -
Page 2160 of 4264
6E-164 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0113 (Flash Code 23) Intake Air Temperature
(IAT) Sensor High Input
Step Action Value (s) Yes No
1
Was the "On-Board Diagnostic (OBD) System Check"
performed?
- Go to Step 2 Go 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 3 Refer 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 4 Refer 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?
E-60(A)
E-61(B)
E-63
- Verify repair Go to Step 5
5
Visually check the IAT sensor.
Was the problem found?
- Go to Step 12 Go to Step 6
Page 2161 of 4264
3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-165
Step Action Value (s) Yes No
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?
MAF & IAT Sensor
Temperature (C) Resistance ()
(Approximately)
-20 15230
0 5760
20 2480
40 1185
60 584
80 332
100 183
120 11 9
Standard
resistance
Go to Step 7
Go 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?
E-63
V
Approximately
5.0V
Go to Step 10
Less 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?
E-60(A)
E-63
- Verify repair Go to Step 14
Page 2162 of 4264
6E-166 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Step Action Value (s) Yes No
9
Repair the short to voltage circuit between the ECM
and IAT sensor.
Was the problem solved?
E-60(A)
E-63
- Verify repair Go to Step 14
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?
E-63
V
Less than 1V
Go to Step 11
Repair 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-95 page.
3. Disconnect the IAT sensor connector.
4. Check the circuit for open circuit.
Was the problem found?
B39
Breaker Box
E-63
Page 2163 of 4264
3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-167
Step Action Value (s) Yes No
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?
E-61(B)
E-63
- Repair faulty
harness and
verify repair Go to Step 14
12
Substitute a known good MAF & IAT sensor assembly
and recheck.
Was the problem solved?
- Go to Step 13 Go to Step 14
13
Replace the MAF & IAT sensor assembly.
Is the action complete?
- Verify repair -
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.
- Verify repair -
Page 2165 of 4264
3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-169
Diagnostic Trouble Code (DTC) P0117 (Flash Code 14) Engine Coolant
Temperature (ECT) Sensor Low Input
Step Action Value (s) Yes No
1 Was the "On-Board Diagnostic (OBD) System Check"
performed?
- Go to Step 2 Go 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 3 Refer 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 4 Refer 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?
E-69
E-60(A)
- Verify repair Go to Step 5
5
Visually check the ECT sensor.
Was the problem found?
- Go to Step 8 Go to Step 6