check engine ISUZU TF SERIES 2004 Workshop Manual

6E-284 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Step Action Value (s) Yes No
16
Using the DVM and check the VSS signal circuit.
1. Ignition "Off", engine "Off".
2. Disconnect the VSS connector and meter
connector.
3. Check the circuit for open or short to ground circuit.
If a open or short to ground circuit is found, repair
the faulty harness and verify repair.
Is the action complete?
E-44




B-24



-
Verify repair
-
17
Replace the speed meter.
Is the action complete?
- Verify repair -
18
Using the DVM and check the VSS signal circuit.
1. Ignition "On", engine "Off".
2. Disconnect the meter connector and immobilizer
control unit connector (if equipped).
3. Check the circuit for short to power supply circuit.
Was the DVM indicated specified value?
B-24
B-68
VV





Less than 1V
Go to Step 19
Repair faulty
harness and
verify repair

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-285
Step Action Value (s) Yes No
19
Using the DVM and check the VSS signal circuit.
1. Ignition "Off", engine "Off".
2. Disconnect the meter connector and immobilizer
control unit connector (if equipped).
3. Check the circuit for open or short to ground circuit.
If a open or short to ground circuit is found, repair the
faulty harness and verify repair.
Is the action complete?
B-24
B-68






-
Verify repair
-
20
Replace the immobilizer control unit (if equipped).
Is the action complete?
- Verify repair -
21
Using the DVM and check the VSS signal circuit.
1. Ignition "Off", engine "Off".
2. Disconnect the immobilizer control unit connector (if
equipped) and ECM connector.
3. Ignition "On".
4. Check the circuit for short to power supply circuit.
Was the DVM indicated specified value?
B-68
V


E-61(B)
V



Less than 1V
Go to Step 22
Repair faulty
harness and
verify repair

6E-286 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Step Action Value (s) Yes No
22

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 (if
equipped).
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 (if
equipped) and ECM connector.
3. Check the circuit for open or short to ground circuit.
Was the problem found?
E-61(B)
B-68










-

Repair faulty
harness and
verify repair

Go to Step 25
23
Substitute a known good VSS and recheck.
Was the problem solved?
- Go to Step 24 Go to Step 25
24
Replace the VSS.
Was the problem solved?
- Verify repair Go to Step 25
25
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 26

6E-288 3.5L ENGINE DRIVEABILITY AND EMISSIONS
DIAGNOSTIC TROUBLE CODE (DTC) P0562 (FLASH CODE 66) SYSTEM
VOLTAGE LOW

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)
66 P0562 D System Voltage Low Battery voltage is below 6V for more than 20 seconds. No fail-safe function.


CIRCUIT DESCRIPTION
The engine control module (ECM) monitors the system
voltage on the ignition feed terminals to the ECM.
A
system voltage DTC will set whenever the voltage is
above a calibrated value.

DIAGNOSTIC AIDS
If the DTC sets when an accessory is operated, check
for a poor connection or defective accessory.


Diagnostic Trouble Code (DTC) P0562 (Flash Code 66)
System Voltage Low
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 P0562 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 P0562 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 "On".
2. Monitor the "Ignition Voltage" in the data display.
3. Load the electrical system by turning on the
headlights, etc..
Does the Tech 2 indicate enough ignition voltage?
10 – 14.5V Go to Step 6 Go to Step 5
5
Using the DVM and check the battery voltage at the
battery terminal.
Does the tester indicate enough battery voltage?
10 – 14.5V Go to Step 6 Check the
charging system,
charge or replace
the battery

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-289
Step Action Value (s) Yes No
6
Check for poor/faulty connection at the ECM
connector. If a poor/faulty connection is found, repair
as necessary.
Was the problem found?
E-60(A)




E-61(B)






- Verify repair Go to Step 7
7
Check for poor/faulty connection of the ECM ground at
the common chamber right and left. If a poor/faulty
connection is found, repair as necessary.
Was the problem found?
E-72/E-73/E-74

- Verify repair Go to Step 8
8
Using the DVM and check the ECM 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. Check the circuit for open circuit.
Was the problem found?
A7Breaker BoxB6 A37 A33 A8







A4

6E-290 3.5L ENGINE DRIVEABILITY AND EMISSIONS
Step Action Value (s) Yes No


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












E-61(B)







-

Repair faulty
harness and
verify repair

Go to Step 9
9
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 10
10
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-291
DIAGNOSTIC TROUBLE CODE (DTC) P0563 (FLASH CODE 66)
SYSTEM VOLTAGE HIGH

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)
66 P0563 A System Voltage High Battery voltage is above 16V for more than 20 seconds. No fail-safe function.

CIRCUIT DESCRIPTION
The engine control module (ECM) monitors the system
voltage on the ignition feed terminals to the ECM.
A
system voltage DTC will set whenever the voltage is
above a calibrated value.
DIAGNOSTIC AIDS
If the DTC sets when an accessory is operated, check
for a poor connection or defective accessory.


Diagnostic Trouble Code (DTC) P0563 (Flash Code 66)
System Voltage 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 P0563 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 P0563 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 "On".
2. Monitor the "Ignition Voltage" in the data display.
3. Load the electrical system by turning on the
headlights, etc..
Does the Tech 2 indicate correct ignition voltage?
Less than 16VGo to Step 5 Check the
charging
system and Go
to Step 5
5
Is the battery jamp start cable incorrectly connecting?
- Verify
procedure Go to Step 6
6
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 7

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-293
DIAGNOSTIC TROUBLE CODE (DTC) P0601 (FLASH CODE 51)
CONTROL MODULE MEMORY CHECKSUM

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)
51 P0601 A Control Module
Memory Checksum ECM memory area error. Engine control disabled.


CIRCUIT DESCRIPTION
The engine control module (ECM) used in this vehicle
utilizes an electrically erasable programmable read-only
memory (EEPROM). The EEPROM contains program
information and the calibrations required for engine,
transmission, and engine diagnostics operation.
Unlike the PROM used in past applications, the
EEPROM is not replaceable.

DIAGNOSTIC AIDS
 DTC P0601 indicates that the contents of the
EEPROM have changed since the ECM was
programmed. The only possible repair is ECM
replacement.


Diagnostic Trouble Code (DTC) P0601 (Flash Code 51)
Control Module Memory Checksum
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 P0601 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 P0601 stored in this ignition cycle?
- Go to Step 4 Refer to
Diagnostic Aids
4
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 5

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-295
DIAGNOSTIC TROUBLE CODE (DTC) P0602 ECU PROGRAMMING ERROR

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)
51 P0602 - ECU Programming
Error ECM memory area error. Engine control disabled.

CIRCUIT DESCRIPTION
The engine control module (ECM) used in this vehicle
utilizes an electrically erasable programmable read-only
memory (EEPROM). The EEPROM contains program
information and the calibrations required for engine,
transmission, and engine diagnostics operation.
Unlike the PROM used in past applications, the
EEPROM is not replaceable.

DIAGNOSTIC AIDS
Check for following conditions.
 When reprogramming operation is stopped unde
r
Service Programming System (SPS), DTC P0602 will
be set.
 When non programmed ECM (service ECM) is used
without Service Programming System (SPS), DTC
P0602 will be set.



Diagnostic Trouble Code (DTC) P0602 ECU Programming Error

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 P0602 stored as "Present Failure"?
- Go to Step 3 Refer to
Diagnostic Aids
3
Download the latest software to the ECM. "SPS
(Service Programming System) is necessary."
Is the action complete?
- Verify repair -

3.5L ENGINE DRIVEABILITY AND EMISSIONS 6E-297
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)
P1508 B Idle Air Control System
Low/Closed 1. No DTC relating to MAF sensor, IAT sensor, ECT sensor,
TPS, CMP sensor, CKP sensor, VSS and system voltage.
2. Engine speed is between 675rpm and 6000rpm.
3. Engine coolant temperature is more than 75
C.
4. Intake air temperature is between -10
C and 80
C.
5. Vehicle is stopping.
6. Small amount of intake air through the idle air control
valve. (Idle air control valve is sticking at close position.)
Above conditions are met for 2 seconds. 22
P1509 B Idle Air Control System
High/Open 1. No DTC relating to MAF sensor, IAT sensor, ECT sensor,
TPS, CMP sensor, CKP sensor, VSS and system voltage.
2. Engine speed is between 675rpm and 6000rpm.
3. Engine coolant temperature more than 75
C.
4. Intake air temperature is between -10
C and 80
C.
5. Vehicle is stopping.
6. Large amount of intake air through the idle air control
valve. (Idle air control valve is sticking at open position.)
Above conditions are met for 2 seconds. Fuel cut is operated at high idle
speed.

CIRCUIT DESCRIPTION
The engine control module (ECM) controls engine idle
speed by adjusting the position of the idle air control
(IAC) motor pintle. The IAC is a bi-directional steppe
r
motor driven by two coils. The ECM applies current to
the IAC coils in steps (counts) to extend the IAC pintle
into a passage in the throttle body to decrease air flow.
The ECM reverses the current to retract the pintle,
increasing air flow. This method allows highly accurate
control of idle speed and quick response to changes in
engine load. If the ECM detects a condition where too
low of an idle speed is present and the ECM is unable
to adjust idle speed by increasing the IAC counts, DTC
P1508 or P1509 will set, indicating a problem with the
idle control system.

DIAGNOSTIC AIDS
Check for the following conditions:
 Poor connection at ECM or IAC motor –Inspec
t
harness connectors for backed-out terminals,
improper mating, broken locks, improperly formed o
r
damaged terminals, and poor terminal-to-wire
connection.
 Damaged harness – Inspect the wiring for damage.
 Restricted air intake system – Check for a possible
collapsed air intake duct, restricted air filter element,
or foreign objects blocking the air intake system.