ignition ISUZU TF SERIES 2004 Workshop Manual

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-321
Step Action Value (s) Yes No
9
Using the DVM and check the VSS signal circuit.
1. Ignition "Off", engine "Off".
2. Disconnect the immobilizer control unit connector
and ECM connector.
3. Ignition "On".
4. Check the circuit for short to power supply circuit.
Was the problem found?
B-68

V

-
Repair faulty
harness and
verify repair
Go to Step 10
10

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-95 page.
3. Disconnect the immobilizer control unit connector .
4. Check the circuit for open or shot to ground circuit.
Was the problem found?
B32
Breaker Box


B-68






Breaker box is not available:
1. Ignition "Off", engine "Off".
2. Disconnect the immobilizer control unit connector
and ECM connector.
3. Check the circuit for open or short to ground circuit.
Was the problem found?
B-68

E-61(B)








-

Repair faulty
harness and
verify repair

Go to Srtep 11

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-323
DIAGNOSTIC TROUBLE CODE (DTC) P1631 IMMOBILIZER WRONG SIGNAL



RTW46EMF000301

Condition For Setting The DTC and Action Taken When The DTC Sets
Flash
Code Code Type DTC Name DTC Setting Condition Fail-Safe (Back Up)
67 P1631 - Immobilizer Wrong
Signal Received response is not correct. 1. Engine does not start.
2. Check engine lamp flash.

CIRCUIT DESCRIPTION
The ECM decides whether that is an abnormality in the
immobilizer control system. DTC P1631 is recorded by
the ECM when received response was not correct.

DIAGNOSTIC AIDS
Check for the following conditions:

Poor connection at Engine Control Module (ECM)
and immobilizer inspect harness connectors for
backed out terminals, improper mating, broken
locks, improperly formed or damaged terminals, and
poor terminal to wire connection.

Damaged harness-inspect the wiring harness for
damage, if the harness appears to be OK,
disconnect the ECM and immobilizer, turn the
ignition "ON" and observe a voltmeter connected to
the suspect driver circuit at the ECM and immobilizer
harness connector while moving connectors and
wiring harnesses relates to the Check Engine Lamp
(MIL). A change in voltage will indicate the location
of the fault.

6E-324 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P1631 Immobilizer Wrong Signal
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 P1631 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 P1631 stored in this ignition cycle?
- Go to Step 4 Refer to
Diagnostic Aids
and Go to Step 4
4
1. Using the Tech 2, ignition "On" and engine "Off".
2. Select "Immobilizer" in the system selection menu
"Body".
3. Select "Read DTC Info Ordered By Priority" in the
"Diagnositic Trouble Code".
Was the any DTC's B0005 or B0006 stored in this
ignition cycle?
- Refer to
"Immobilizer
Workshop
Manual" & Go to
DTC Chart
B0005 or B0006 Go to Step 5
5
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 6
6
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 -

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-325
DIAGNOSTIC TROUBLE CODE (DTC) P1648 WRONG SECURITY CODE
ENTERED



RTW46EMF000301

Condition For Setting The DTC and Action Taken When The DTC Sets
Flash
Code Code Type DTC Name DTC Setting Condition Fail-Safe (Back Up)
67 P1648 - Wrong Security Code
Entered Received incorrect security code. 1. Engine does not start.
2. Check engine lamp flash.

CIRCUIT DESCRIPTION
The ECM decides whether that is an abnormality in the
immobilizer control system. DTC P1648 is recorded by
the ECM when received security code was not correct.

DIAGNOSTIC AIDS
Check for the following conditions:

Poor connection at Engine Control Module (ECM)
and immobilizer inspect harness connectors for
backed out terminals, improper mating, broken
locks, improperly formed or damaged terminals, and
poor terminal to wire connection.

Damaged harness-inspect the wiring harness for
damage, if the harness appears to be OK,
disconnect the ECM and immobilizer, turn the
ignition "ON" and observe a voltmeter connected to
the suspect driver circuit at the ECM and immobilizer
harness connector while moving connectors and
wiring harnesses relates to the Check Engine Lamp
(MIL). A change in voltage will indicate the location
of the fault.

6E-326 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P1648 Wrong Security Code Entered
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 P1648 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 P1648 stored in this ignition cycle?
- Go to Step 4 Refer to
Diagnostic Aids
and Go to Step 4
4
1. Using the Tech 2, ignition "On" and engine "Off".
2. Select "Immobilizer" in the system selection menu
"Body".
3. Select "Read DTC Info Ordered By Priority" in the
"Diagnositic Trouble Code".
Was the any DTC's B0002 or B0003 stored in this
ignition cycle?
- Refer to
"Immobilizer
Workshop
Manual" & Go to
DTC Chart
B0002 or B0003 Go to Step 5
5
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 6
6
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 -

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-327
DIAGNOSTIC TROUBLE CODE (DTC) P1649 IMMOBILIZER FUNCTION
NOT PROGRAMMED



RTW46EMF000301

Condition For Setting The DTC and Action Taken When The DTC Sets
Flash
Code Code Type DTC Name DTC Setting Condition Fail-Safe (Back Up)
67 P1649 - Immobilizer Function
Not Programmed Immobilizer function is not programmed in the ECM. 1. Engine does not start.
2. Check engine lamp flash.

CIRCUIT DESCRIPTION
The ECM decides whether that is an abnormality in the
immobilizer control system. DTC P1649 is recorded by
the ECM when immobilizer function was no
t
programmed in the ECM.

DIAGNOSTIC AIDS
Check for the following conditions:

Poor connection at Engine Control Module (ECM)
and immobilizer inspect harness connectors for
backed out terminals, improper mating, broken
locks, improperly formed or damaged terminals, and
poor terminal to wire connection.

Damaged harness-inspect the wiring harness for
damage, if the harness appears to be OK,
disconnect the ECM and immobilizer, turn the
ignition "ON" and observe a voltmeter connected to
the suspect driver circuit at the ECM and immobilizer
harness connector while moving connectors and
wiring harnesses relates to the Check Engine Lamp
(MIL). A change in voltage will indicate the location
of the fault.

6E-328 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P1649 Immobilizer Function
Not Programmed
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 P1649 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 P1649 stored in this ignition cycle?
- Go to Step 4 Refer to
Diagnostic Aids
and Go to Step 4
4
1. Using the Tech 2, ignition "On" and engine "Off".
2. Select "Immobilizer" in the system selection menu
"Body".
3. Select "Read DTC Info Ordered By Priority" in the
"Diagnositic Trouble Code".
Was the DTC B0007 stored in this ignition cycle?
- Refer to
"Immobilizer
Workshop
Manual" & Go to
DTC Chart
B0007 Go to Step 5
5
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 6
6
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 -

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-329
SYMPTOM DIAGNOSIS
PRELIMINARY CHECKS
Before using this section, perform the "On-Board
Diagnostic (OBD) System Check" and verify all of the
following items:

The engine control module (ECM) and check engine
lamp (MIL=malfunction indicator lamp) are operating
correctly.

There are no Diagnostic Trouble Code(s) stored.

Tech 2 data is within normal operating range. Refer
to Typical Scan Data Values.

Verify the customer complaint and locate the correct
symptom in the table of contents. Perform the
procedure included in the symptom chart.

VISUAL/PHYSICAL CHECK
Several of the symptom procedures call for a careful
visual/physical check. This can lead to correcting a
problem without further checks and can save valuable
time. This check should include the following items:

ECM grounds for cleanliness, tightness and proper
location.

Vacuum hoses for splits, kinks, and proper
connection. Check thoroughly for any type of leak or
restriction.

Air intake ducts for collapsed or damaged areas.

Air leaks at throttle body mounting area, manifold
absolute pressure (MAP) sensor and intake manifold
sealing surfaces.

Ignition wires for cracking, harness, and carbon
tracking.

Wiring for proper connections, pinches and cuts.

INTERMITTENT
Important: An intermittent problem may or may not turn
on the check engine lamp (MIL=malfunction indicato
r
lamp) or store a Diagnostic Trouble Code. Do NOT use
the Diagnostic Trouble Code (DTC) charts fo
r
intermittent problems.
The fault must be present to locate the problem.
Most intermittent problems are cased by faulty electrical
connections or wiring. Perform a careful visual/physical
check for the following conditions.

Poor mating of the connector halves or a terminal
not fully seated in the connector (backed out).

Improperly formed or damaged terminal.


All connector terminals in the problem circuit should
be carefully checked for proper contact tension.

Poor terminal-to-wire connection. This requires
removing the terminal form the connector body to
check.

Ignition coils shorted to ground and arcing at ignition
wires or plugs.

Check engine lamp (MIL=malfunction indicator lamp)
wire to ECM shorted to ground.

Poor ECM grounds. Refer to the ECM wiring
diagrams.

Road test the vehicle with a Digital Multimete
r
connected to a suspected circuit. An abnormal voltage
when the malfunction occurs is a good indication tha
t
there is a fault in the circuit being monitored.
Using Tech 2 to help detect intermittent conditions. The
Tech 2 have several features that can be used to
located an intermittent condition. Use the following
features to find intermittent faults:
To check for loss of diagnostic code memory,
disconnect the mass air flow (MAF) sensor and idle the
engine until the check engine lamp (MIL=malfunction
indicator lamp) comes on. Diagnostic Trouble Code
P0102 should be stored and kept in memory when the
ignition is turned OFF.
If not, the ECM is faulty. When this test is completed,
make sure that you clear the Diagnostic Trouble Code
P0102 from memory.

An intermittent check engine lamp (MIL=malfunction
indicator lamp) with no stored Diagnostic Trouble Code
may be caused by the following:

Ignition coil shorted to ground and arcing at ignition
wires or plugs.

Check engine lamp (MIL=malfunction indicator lamp)
wire to ECM short to ground.

Poor ECM grounds. Refer to the ECM wiring
diagrams.

Check for improper installation of electrical options such
as light, cellular phones, etc. Check all wires from ECM
to the ignition control module for poor connections.
Check for an open diode across the A/C compresso
r
clutch and check for other open diodes (refer to wiring
diagrams in Electrical Diagnosis).

6E-332 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Step Action Value (s) Yes No
8
1. Using a Tech 2, display the IAC value.
2. Check for a faulty, plugged, or sticking IAC
operation.
Was the problem found?
- Verify repair Go to Step 9
9
Check the CKP sensor signal or installation condition.
Refer to DTC P0336 "Crankshaft Position Sensor
Circuit Range/Performance" and DTC P0337
"Crankshaft Position Sensor Circuit No Signal".
Was a problem found?
- Verify repair Go to Step 10
10
Check for proper ignition voltage output with the spark
tester.
Was a problem found?
- Verify repair Go to Step 11
11
1. Remove the spark plugs and check for gas or oil
fouling cracks, wear, improper gap, burned
electrodes, heavy deposits, or improper heat
range.
2. If spark plugs are fouled, the cause of fouling must
be determined before replacing the spark plugs.
Was a problem found?
- Verify repair Go to Step 12
12
Check the fuel pressure. Refer to Fuel System
Diagnosis.
Was a problem found?
- Verify repair Go to Step 13
13
Perform the procedure in Fuel System Pressure Test
to determine if there is a problem with fuel delivery.
Was a problem found?
- Verify repair Go to Step 14
14
Visually/physically check the vacuum hose for splits,
kinks and proper connections and routing.
Was a problem found?
- Verify repair Go to Step 15
15
Check the exhaust system for a possible restriction:

Damaged or collapsed pipes.

Internal muffler failure.
Was a problem found?
- Verify repair Go to Step 16
16
Check for the following engine mechanical problems
(refer to Engine Mechanical section):

Low compression.

Leaking cylinder head gaskets.

Worn camshaft.

Camshaft drive belt slipped or stripped.
Was a problem found?
- Verify repair Go to Step 17

6E-334 3.5L ENGINE DRIVEABILITY AND EMISSIONS
HARD START SYMPTOM
DEFINITIONS: Engine cranks, but does not start for a
long time. Does eventually start, or may start and then
immediately stall.



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. Perform a bulletin search.
2. If a bulletin that addresses the symptom is found,
correct the condition as instructed in the bulletin.
Was a bulletin found that addresses the symptom?
- Verify repair Go to Step 3
3
Was a visually/physical check performed?
- Go to Step 4 Go to Visual /
physical Check
4
1. Using a Tech 2, display the ECT sensor and IAT
sensor value.
2. Check the specified value or wire.
Was the problem found?
- Verify repair Go to Step 5
5
Check the ECM grounds to verify that they are clean
and tight. Refer to the ECM wiring diagrams.
Was a problem found?
- Verify repair Go to Step 6
6
Visually/physically inspect for the following conditions:

Restrict air intake system. Check for a restricted air
filter element, or foreign objects blocking the air
intake system.

Check for objects blocking the IAC passage or
throttle bore, excessive deposits in the throttle bore
and on the throttle plate.

Check for a condition that causes a large vacuum
leak, such as an incorrectly installed or faulty
crankcase ventilation hose/brake booster hose.
Was a problem found?
- Verify repair Go to Step 7
7
1. Using a Tech 2, display the IAC value.
2. Check for a faulty, plugged, or sticking IAC
operation.
Was the problem found?
- Verify repair Go to Step 8
8
Check the CKP sensor signal or installation condition.
Refer to DTC P0336 "Crankshaft Position Sensor
Circuit Range/Performance" and DTC P0337
"Crankshaft Position Sensor Circuit No Signal".
Was a problem found?
- Verify repair Go to Step 9
9
Check for proper ignition voltage output with a spark
tester.
Was the problem found?
- Verify repair Go to Step 10