power ISUZU TF SERIES 2004 Workshop Manual

4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E –139
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?
Less than 1V Go to Step 9 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 —
Step Action Value(s) Yes No
5
V
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6E–146 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
6 Using the DVM and check the vacuum pressure
sensor signal circuit.
Breaker box is available:
1 . I g n i t i o n " O f f " , e n g i n e " O f f " .
2. Install the breaker box as type A. (ECM
disconnected) Ref. Page 6E-103
3. Disconnect the vacuum pressure sensor
connector.
4. Check the circuit for open, short to sensor ground
or short to ground circuit.
Was the problem found?
Breaker box is not available:
1 . I g n i t i o n " O f f " , e n g i n e " O f f " .
2. Disconnect the vacuum pressure sensor
connector and ECM connector.
3. Check the circuit for open, short to sensor ground
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 vacuum pressure
sensor power supply circuit.
1. Ignition "On", engine "Off".
2. Disconnect the vacuum pressure sensor
connector.
3. Check the circuit for open circuit.
Was the DVM indicated specified value?
Approx imately
5.0V
Go to Step 9Go to Step 8
85
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6E–148 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0105 (Symptom Code 7) (Flash Code 34)
Vacuum Pressure Sensor Voltage Supply Circuit High Input
Step Action 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 As Stored By ECU" in
"F0: Diagnostic Trouble Codes".
Is the DTC P0105 (Symptom Code 7) stored as
"Present Failure"? - Go to Step 3Refer to
Diagnostic Aids
and Go to Step
3
3 1. Using the Tech 2, ignition "On" and engine "Off".
2. Select "F1: Clear DTC Information" in "F0:
Diagnostic Trouble Codes" with the Tech 2 and
c l e a r t h e D T C i n f o r m a t i o n .
3. Operate the vehicle and monitor the "F0: Read
DTC Infor As Stored By ECU" in the "F0:
Diagnostic Trouble Codes".
Was the DTC P0105 (Symptom Code 7) 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 vacuum
pressure 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 V i s u a l l y c h e c k t h e v a c u u m p r e s s u r e s e n s o r .
Was the problem found? - Go to Step 8Go to Step 6
6 Using the DVM and check the vacuum pressure
sensor power supply circuit.
1. Ignition "On", engine "Off".
2. Disconnect the vacuum pressure sensor
connector.
3. Check the circuit for short to battery voltage
circuit.
Was the DVM indicated specified value?
Approx imately
5.0V
Go to Step 8Go to Step 7
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6E–150 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0105 (Symptom Code 9) (Flash Code 34)
Vacuum Pressure Sensor Voltage Supply Circuit Low Input
Step Action 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 As Stored By ECU" in
"F0: Diagnostic Trouble Codes".
Is the DTC P0105 (Symptom Code 9) stored as
"Present Failure"? - Go to Step 3Refer to
Diagnostic Aids
and Go to Step
3
3 1. Using the Tech 2, ignition "On" and engine "Off".
2. Select "F1: Clear DTC Information" in "F0:
Diagnostic Trouble Codes" with the Tech 2 and
c l e a r t h e D T C i n f o r m a t i o n .
3. Operate the vehicle and monitor the "F0: Read
DTC Infor As Stored By ECU" in the "F0:
Diagnostic Trouble Codes".
Was the DTC P0105 (Symptom Code 9) 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 vacuum
pressure 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 V i s u a l l y c h e c k t h e v a c u u m p r e s s u r e s e n s o r .
Was the problem found? - Go to Step 10Go to Step 6
6 Using the DVM and check the vacuum pressure
sensor power supply circuit.
1. Ignition "On", engine "Off".
2. Disconnect the vacuum pressure sensor
connector.
3 . C h e c k t h e c i r c u i t f o r s h o r t t o g r o u n d c i r c u i t .
Was the DVM indicated specified value?
Approx imately
5.0V
Go to Step 10Go to Step 7
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4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–151
7 Using the DVM and check the vacuum pressure
sensor power supply circuit.
1 . I g n i t i o n " O f f " , e n g i n e " O f f " .
2. Disconnect the vacuum pressure sensor
connector and ECM connector.
3. Check the circuit for short to vacuum pessure
sensor ground circuit.
Was the DVM indicated specified value?
No continuity Go to Step 9Go to Step 8
8 Repair the circuit for short to vacuum pressure sensor
ground.
Is the action complete? - Verify repair -
9 Repair the short to ground circuit between the vacuum
p r e s s u r e s e n s o r.
Was the problem solved? - Verify repair Go to Step 12
10 Substitute a known good MAF & IAT sensor assembly
a n d re ch e c k.
Was the problem solved? - Go to Step 11Go to Step 12
11 R e p l a c e t h e M A F & I A T s e n s o r a s s e m b l y .
Is the action complete? - Verify repair -
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
1 3 R e p l a c e t h e E C M .
I s t h e a c t i o n c o mp l e t e ?
IMPORTANT: The replacement ECM must be
programmed. Refer to section of the Service
Programming System (SPS) in this manual.
Following ECM programming, the immobiliser 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 -
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4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E –155
9 Repair the short to voltage circuit between the ECM
and IAT sensor.
Was the problem solved?
— 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 MAF & 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 11 Repair faulty
harness and verify repair
Step Action Value(s) Yes No
1
84
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4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E –163
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 11 Repair faulty
harness and verify repair
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) Ref. Page 6E-103
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 ECM connector.
3. Check the circuit for open circuit.
Was the problem found?
— Repair faulty
harness and verify repair Go to Step 14
Step Action Value(s) Yes No
891
E-41
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2
V
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2
93
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6E–188 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
Step Action Value(s) Yes No
6Using the DVM and check the wastegate control
solenoid power supply circui t.
1 . I g n i t i o n " O n " , e n g i n e " O f f " .
2. Remove the wastegate control solenoid
connector.
3 . C h e c k t h e c i r c u i t f o r o p e n c i r c u i t .
Was the DVM indicated specified value? 10 - 14.5V Go to Step 8Go to Step 7
7Repair the open circuit between the ECM main relay
and wastegate control solenoid.
Is the action complete? - Verify repair -
8Using the DVM and check the wastegate control
solenoid circuit.
Breaker box is available:
1. Ignition "Off", engine "Off".
2. Install the breaker box as type A. (ECM
disconnected) Ref. Page 6E-103
3. Remove the wattage control solenoid 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. Remove the wastegate control solenoid
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 11
9Substitute a known good wastegate control solenoid
a n d re ch e c k.
Was the problem solved? - Go to Step 10Go to Step 11
10Replace the wastegate control solenoid.
Is the action complete? - Verify repair -
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4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–191
Step Action Value(s) Yes No
10Check for poor/faulty connection at the vacuum
pressure sensor or ECM connector. If a poor/faulty
connection is found, repair as necessary.
Was the problem found?
- Verify repair Go to Step 11
11V i s u a l l y c h e c k t h e v a c u u m p r e s s u r e s e n s o r .
Was the problem found? - Go to Step 13Go to Step 12
12Using the DVM and check the vacuum pressure
sensor signal circuit.
1. Ignition "On", engine "Off".
2. Disconnect the vacuum pressure sensor
connector.
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
13Substitute a known good vacuum pressure sensor
a s s e m b l y a n d r e c h e c k .
Was the problem solved? - Go to Step 14Go to Step 15
14Replace the vacuum pressure sensor assembly.
Is the action complete? - Verify repair -
15Is 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 16
16R e p l a c e t h e E C M .
I s t h e a c t i o n c o mp l e t e ?
IMPORTANT: The replacement ECM must be
programmed. Refer to section of the Service
Programming System (SPS) in this manual.
Following ECM programming, the immobiliser 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 -
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4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–193
Step Action Value(s) Yes No
9Using 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?
Less than 1V Go to Step 12Repair faulty
harness and
verify repair
10Substitute a known good MAF & IAT sensor assembly
a n d re ch e c k.
Was the problem solved? - Go to Step 11Go to Step 12
11Replace the MAF & IAT sensor assembly.
Is the action complete? - Verify repair -
12Is 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
13R e p l a c e t h e E C M .
I s t h e a c t i o n c o mp l e t e ?
IMPORTANT: The replacement ECM must be
programmed. Refer to section of the Service
Programming System (SPS) in this manual.
Following ECM programming, the immobiliser 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 -
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