ignition ISUZU TF SERIES 2004 Workshop Manual

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-265
Step Action Value (s) Yes No
6
Using the DVM and check the EGR valve position
sensor.
1. Ignition "Off", engine "Off".
2. Disconnect EGR valve connector.
3. Measure the resistance of EGR valve position
sensor.
Does the tester indicate standard resistance as shown
in the following table?
EGR Valve



EGR Valve









Measurement Terminal Resistance ()
2 – 3 Approximately 1.1k
3 – 4 Approximately 4.5k
2 - 4 Approximately 4.7k
Standard
resistance
Go to Step 7
Go to Step 10
7
Using the DVM and check the EGR valve position
sensor power supply circuit.
1. Ignition "On", engine "Off".
2. Disconnect the EGR valve connector.
3. Check the circuit for open or short to ground circuit.
Was the DVM indicated specified value?
E-76
V



Approximately
5.0V
Go to Step 9
Go to Step 8
8
Repair the open or short to ground circuit between the
ECM and EGR valve position sensor circuit.
Was the problem solved?
E-76


E-60(A)


- Verify repair Go to Step 12

6E-266 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Step Action Value (s) Yes No
9

Using the DVM and check the EGR valve position
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 EGR valve connector.
4. Check the circuit for open, short to sensor ground
or short to ground circuit.
Was the problem found?
E-76





A9A22


Breaker Box




Breaker box is not available:
1. Ignition "Off", engine "Off".
2. Disconnect the EGR valve connector and ECM
connector.
3. Check the circuit for open, short to sensor ground
or short to ground circuit.
Was the problem found?
E-76


E-60(A)










-

Repair faulty
harness and
verify repair

Go to Step 10
10
Substitute a known good EGR valve and recheck.
Was the problem solved?
- Go to Step 11 Go to Step 12
11
Replace the EGR valve.
Is the action complete?
- Verify repair -

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-269
Diagnostic Trouble Code (DTC) P0406 (Flash Code 32)
EGR Circuit High

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 P0406 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 P0406 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 EGR valve or
ECM connector. If a poor/faulty connection is found,
repair as necessary.
Was the problem found?
E-60(A)
E-76





- Verify repair Go to Step 5
5
Visually check the EGR valve.
Was the problem found?
- Go to Step 12 Go to Step 6

6E-270 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Step Action Value (s) Yes No
6
Using the DVM and check the EGR valve position
sensor.
1. Ignition "Off", engine "Off".
2. Disconnect EGR valve connector.
3. Measure the resistance of EGR valve position
sensor.
Does the tester indicate standard resistance as shown
in the following table?
EGR Valve



EGR Valve









Measurement Terminal Resistance ()
2 – 3 Approximately 1.1k
3 – 4 Approximately 4.5k
2 - 4 Approximately 4.7k
Standard
resistance
Go to Step 7
Go to Step 12
7
Using the DVM and check the EGR position sensor
power supply circuit.
1. Ignition "On", engine "Off".
2. Disconnect the EGR valve connector.
3. Check the circuit for short to voltage circuit.
Was the DVM indicated specified value?
E-76
V



Approximately
5.0V
Go to Step 9
Go to Step 8
8
Repair the short to voltage circuit between the ECM
and EGR valve.
Was the problem solved?
E-76


E-60(A)


- Verify repair Go to Step 14

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-271
Step Action Value (s) Yes No
9
Using the DVM and check the EGR position sensor
signal circuit.
1. Ignition "On", engine "Off".
2. Disconnect the EGR valve connector.
3. Check the circuit for short to power supply circuit.
Was the DVM indicated specified value?
E-76
V




Less than 1V
Go to Step 10
Repair faulty
harness and
verify repair
10
Using the DVM and check the EGR position sensor
ground circuit.
1. Ignition "On", engine "Off".
2. Disconnect the EGR valve connector.
3. Check the circuit for short to power supply circuit.
Was the DVM indicated specified value?
E-76
V




Less than 1V
Go to Step 11
Repair faulty
harness and
verify repair

6E-272 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Step Action Value (s) Yes No
11

Using the DVM and check the EGR position 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 EGR valve connector.
4. Check the circuit for open circuit.
Was the problem found?
A22
Breaker Box
E-76






Breaker box is not available:
1. Ignition "Off", engine "Off".
2. Disconnect the EGR valve connector and ECM
connector.
3. Check the circuit for open circuit.
Was the problem found?
E-60(A)
E-76










-

Repair faulty
harness and
verify repair

Go to Step 12
12
Substitute a known good EGR valve and recheck.
Was the problem solved?
- Go to Step 13 Go to Step 14
13
Replace the EGR valve.
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

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-275
CIRCUIT DESCRIPTION
The canister purge solenoid valve is controlled by the
Engine Train Control Module (ECM).
At an appropriate time, the EVAP canister purge
solenoid is “ON," allowing engine vacuum to draw a
small vacuum on the entire evaporative emissions
system.
DIAGNOSTIC AIDS
An intermittent may be caused by the following:
 Poor connections.
 Mis routed harness.
 Rubbed through wire insulation.
 Broken wire inside the insulation.
Check for the following conditions:

 Poor connection at ECM-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 fo
r
damage. If the harness appears to be OK, observe
the EVAP purge solenoid display on the Tech 2 while
moving connectors and wiring harnesses related to
the sensor.
A change in the display will indicate the location o
f
the fault. If DTC P0444 or P0445 cannot be
duplicated, the information included in the Failure
Records data can be useful in determined vehicle
mileage since the DTC was last set.
If it is determined that the DTC occurs intermittently,
performing the DTC P0444 or P0445 Diagnostic
Chart may isolate the cause of the fault.


Diagnostic Trouble Code (DTC) P0444 EVAP Purge Solenoid
Valve Circuit Low Voltage
Diagnostic Trouble Code (DTC) P0445 EVAP Purge Solenoid
Valve Circuit High Voltage

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 P0444 or P0445 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 P0444 or P0445 stored in this ignition
cycle?
- Go to Step 4 Refer to
Diagnostic Aids
and Go to Step 4

6E-276 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Step Action Value (s) Yes No
4
Check for poor/faulty connection at the purge solenoid
valve or ECM connector. If a poor/faulty connection is
found, repair as necessary.
Was the problem found?
E-61(B)
E-66




- Verify repair Go to Step 5
5
Using the DVM and check the purge solenoid valve.
1. Ignition "Off", engine "Off".
2. Disconnect purge solenoid valve connector.
3. Measure the resistance of purge solenoid valve
coil.
Does the tester indicate standard resistance?
25 - 30
at
20C
Go to Step 6
Go to Step 9
6
Using the DVM and check the purge solenoid valve
power supply circuit.
1. Ignition "On", engine "Off".
2. Disconnect the purge solenoid valve connector.
3. Check the circuit for open circuit.
Was the DVM indicated specified value?
E-66
V




10-14.5V
Go to Step 8
Go to Step 7
7
Repair the open or short to ground circuit between the
"Engine" fuse (15A) and purge solenoid valve.
Is the action complete?
- Verify repair -

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-277
Step Action Value (s) Yes No
8

Using the DVM and check the purge solenoid valve
solenoid 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 purge solenoid valve connector.
4. Check the circuit for open or short to ground circuit.
Was the problem found?
B15
Breaker BoxE-66







Breaker box is not available:
1. Ignition "Off", engine "Off".
2. Disconnect the purge solenoid valve connector and
ECM connector.
3. Check the circuit for open or short to ground circuit.
Was the problem found?
E-61(B)
E-66











-

Repair faulty
harness and
verify repair

Go to Step 9

6E-278 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Step Action Value (s) Yes No
9
Using the DVM and check the purge solenoid valve
signal circuit.
1. Ignition "On", engine "Off".
2. Disconnect the purge solenoid valve connector.
3. Check the circuit for short to battery voltage circuit.
Was the DVM indicated battery voltage?
E-66
V




-
Repair faulty
harness and
verify repair
Go to Step 10
10
Substitute a known good purge solenoid valve and
recheck.
Was the problem solved?
- Go to Step 11 Go to Step 12
11
Replace the purge solenoid valve.
Was the problem solved?
- Verify repair Go to Step 12
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
13
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 -