ECU ISUZU TF SERIES 2004 Repair Manual

4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–101
5. After choosing the data, click the “Nex t” button.
6. When all the necessary information is entered, the
“details” of software within the database that match
the entered data will appear for confirmation. Click
the “Program” switch and then download the new
software onto Tech-2.
7.“Data Transfer” comes on display. The progress of
downloading will be displayed on the screen in the
form of bar graph.
8. Upon finishing the data transfer, turn off the power
of Tech-2, removing from P/C.4. Programming of ECM
1. Check to see if batteries are fully charged, while
ABS connectors shall be removed from the vehicle.
2. Connect Tech-2 to Vehicle Diagnostic Connectors.
3. Turn on the power of Tech-2 and the title screen
comes on display.
4. Turn on the ignition (without allowing the engine to
start)
5. On the title screen of Tech-2, push the “Enter”
button.
6. Choose “F1: Service Programming System” on the
main screen and then choose “Fl: Program ECU”.
7. While data is being transferred, “Programming in
Progress” will be displayed on the Tech-2 screen.
8. Upon finishing the data transfer, Tech-2 will display
“Reprogramming Was Successful”. Push the “Exit”
button to bring program to completion
9. Following “Procedure 2: Demand of Data”, try over
again “Information Obtaining” and check to confirm
if the data has been correctly re-loaded.
10. Upon finishing confirmation, turn off the ignition of
the vehicle and then turn off the power of Tech-2,
removing from the vehicle.

6E–106 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
6. The Tech2 parameters which is not within the typical
range may help to isolate the area which is causing the
problem.12. This vehicle is equipped with ECM which utilizes an
electrically erasable programmable read only memory
(EEPROM).
On-Board Diagnostic (OBD) System Check
Step Action Value(s) Yes No
11. Ignition “On”, engine “Off”.
2. Check the “CHECK ENGINE” lamp (MIL).
Does the “CHECK ENGINE” lamp turn “On”?—Go to Step 2Go to No
CHECK
ENGINE Lamp
21. Using the Tech 2, ignition “On” and engine “Off”.
2. Attempt to display “Data Display” with the Tech 2.
Does the Tech 2 display engine data? —Go to Step 3Go to Step 7
31. Using the Tech 2, ignition “On” and engine “Off”.
2. Select the “Miscellaneous Test” and perform the
“Check Light” in “Lamps”.
3. Operate the Tech 2 in accordance with the Tech 2
instructions.
Does the “CHECK ENGINE” lamp turn “Off”? —Go to Step 4Go to CHECK
ENGINE LAMP
On Steady
4Attempt to start the engine.
Does the engine start and continue to “Run”?
—Go to Step 5Go to Engine
Cranks But Will
Not Run
51. Using the Tech 2, ignition “On” and engine “Off”.
2. Select the “Read DTC Infor As Stored By ECU” in
“Diagnostic Trouble Code”.
3. Are any DTCs stored?—Go to DTC
ChartGo to Step 6
6Compare typical scan data values displayed on the
Te c h 2 “Data Display”.
Are the displayed values within the range?—Refer to
SYMPTOM
DIAGNOSISRefer to
TYPICAL
SCAN DATA
7Using the DVM and check the data link connector
power supply circuit.
1. Ignition “Off”, engine “Off”.
2. Check the circuit for open circuit.
Was the problem found?
—Repair faulty
harness and
verify repair Go to Step 8
V
B-58

6E–122 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
35 P0560 A OFF System Voltage Malfunction System voltage of PSG
(pump control unit) is below
4.5V or more than 27V.PSG uses default voltage as
substitute.System voltage of PSG is
between 4.5V and 27V.1. Battery power feed
harness open circuit or
short to ground circuit.
2. PSG (pump control unit)
ground harness open or
p o o r c o n n e c t i o n .
3. Poor connector
c o n n e c t i o n .
4 . B a t t e r y m a l f u n c t i o n .
5. Charge system
m a l f u n c t i o n .
6. Battery jump start cable
misconnect.
7. PSG (pump control unit)
malfunction.——
18 P0561 A OFF Ignition Switch Circuit
MalfunctionThe ECM recognized ignition
switch turn off signal during
ECM is activated.ECM stops engine. No recovery until condition
match in the next ignition key
cycle.1. Ignition switch circuit
open or short to ground
c i r c u i t .
2. Poor connector
c o n n e c t i o n .
3. Ignition switch
m a l f u n c t i o n .
4. ECM malfunction.39 —
B OFF Ignition Switch Circuit
MalfunctionIgnition switch circuit is
malfunction.1. Ignition switch circuit
open or short to ground
c i r c u i t .
2. Poor connector
c o n n e c t i o n .
3. Ignition switch
m a l f u n c t i o n .
4. ECM malfunction.39 —
- P0602 - Control Module
Programming ErrorECM memory area error. Engine control disabled. Memory are is OK. ECM is not programmed.
——
28 P0606 A ON ECU Malfunction Gate Array communication
error.1. MAB (fuel cutoff solenoid
v a l v e ) i s o p e r a t e d .
2. Desired injection quantity
becomes 0mg/strk.No recovery. ECM malfunction.
——
B ON ECU Malfunction 1. Throttle position is below
1 % .
2. Desired injection quantity
is more than 0mg/strk.
3. Engine speed is more
t h a n 2 0 0 0 r p m . MAB (fuel cutoff solenoid
v a l v e ) i s o p e r a t e d . Desired injection quantity is
b e l o w 0 m g / s t r k . 1 . E C M m a l f u n c t i o n .
2. PSG (pump control unit)
malfunction.
—— Flash
CodeCodeSymptom
CodeMILDTC Name DTC Setting Condition Fail-Safe (Back Up) Recovery Condition Related Failure PartsRelated
ECM Pin
No.Related
Multiple
DTC4JA1-TC
(MT)4JH1-TC
(MT)4JH1-TC
(AT)

4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–125
43 P1335 A ON Engine Speed Output Circuit
MalfunctionThe PSG (pump control unit)
is recognized defective
engine speed signal form the
ECM.Fuel injection quantity is
reduced.Correct engine speed signal. 1. CKP sensor harness
open circuit, short to
ground or short to
voltage.
2. CKP sensor output
harness open circuit,
short to ground or short
t o v o l t a g e .
3. Poor connector
c o n n e c t i o n .
4. CKP sensor malfunction.
5. Pulse sensing gap
i n c o r r e c t .
6 . P u l s e r m a l f u n c t i o n .
7. Electrical interference.
8. Magnetic interference.
9. ECM malfunction.
10. PSG (pump control unit)
malfunction.9 0 /
9 1 /
9 8 /
101P0335(B)/











P0335(D)
45 P1345 A ON Camshaft Speed Malfunction The PSG (pump control unit)
is recognized incorrect
camshaft speed signal.No fail-safe function. Correct camshaft speed. 1. Pump camshaft speed
s e n s o r m a l f u n c t i o n .
2. Pulse sensing gap
i n c o r r e c t .
3 . P u l s e r m a l f u n c t i o n .
4. Electrical interference.
5. Magnetic interference.
6. ECM malfunction.
7. PSG (pump control unit)
malfunction.——
47 P1520 A ON Neutral Switch ON Error Neutral switch signal is
inputted "On" three times
consecutively under driving
conditions.No fail-safe function. Correct neutral switch signal
is inputted two times
consecutively under driving
conditions.1. Neutral switch circuit
short to voltage circuit.
2. Neutral switch
m a l f u n c t i o n .
3. ECM malfunction.87 —
B ON Neutral Switch OFF Error Neutral switch signal is
inputted "Off" three times
consecutively under driving
conditions.1. Neutral switch circuit
open, short to ground
c i r c u i t .
2. Poor connector
c o n n e c t i o n .
3. Neutral switch
m a l f u n c t i o n .
4. ECM malfunction.87 — —
55 P1605 C ON Seed and Key File Destroyed Seed or key file in EEPROM
is destroyed.No fail-safe function. No recovery. ECM malfunction.
——
D ON EEPROM Defect Write and read from the
EEPROM are failed during
initialization of the ECM.ECM uses default values
from the EPROM.Write and read from the
EEPROM are correct during
initialization of the ECM.ECM malfunction.
—— Flash
CodeCodeSymptom
CodeMILDTC Name DTC Setting Condition Fail-Safe (Back Up) Recovery Condition Related Failure PartsRelated
ECM Pin
No.Related
Multiple
DTC4JA1-TC
(MT)4JH1-TC
(MT)4JH1-TC
(AT)

6E–126 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
55 P1605 E ON EEPROM Defect EEPROM checksum does
not match with the read
check sum during
initialization of the ECM.EEPROM checksum match
with the read check sum
during initialization of the
ECM.ECM malfunction.
——
56 P1610 A - Security Key and Security
Code not ProgrammedImmobilizer functions are not
programmed in the ECM.1 . E n g i n e d o e s n o t s t a r t .
2. Check engine lamp flash. No recovery. ECM malfunction.
— B****
56 P1611 A - Wrong Security Code
EnteredReceived security code is not
correct.1 . E n g i n e d o e s n o t s t a r t .
2. Check engine lamp flash. N o r e c o v e r y . 1 . E C M m a l f u n c t i o n .
2. Immobilizer control unit
m a l f u n c t i o n .
3. Transponder key
malfunction.— B****
56 P1612 A - Immobilizer No or Wrong
SignalReceived challenge signal is
not correct or not received.1 . E n g i n e d o e s n o t s t a r t .
2. Check engine lamp flash. No recovery. 1. ECM and immobilizer
control unit
communication circuit
open circuit, short to
ground circuit or short to
voltage circuit.
2 . E C M m a l f u n c t i o n .
3. Immobilizer control unit
m a l f u n c t i o n .
4. Transponder key
malfunction.2 7 /
35B****
56 P1613 A - Immobilizer No or Wrong
SignalReceived response signal is
not correct or not received.1 . E n g i n e d o e s n o t s t a r t .
2. Check engine lamp flash. No recovery. 1. ECM and immobilizer
control unit
communication circuit
open circuit, short to
ground circuit or short to
voltage circuit.
2 . E C M m a l f u n c t i o n .
3. Immobilizer control unit
m a l f u n c t i o n .
4. Transponder key
malfunction.2 7 /
35B****
56 P1614 A - Wrong Transponder Key Received response signal is
not correct from the
transponder key.1 . E n g i n e d o e s n o t s t a r t .
2. Check engine lamp flash. N o r e c o v e r y . 1 . E C M m a l f u n c t i o n .
2. Immobilizer control unit
m a l f u n c t i o n .
3. Transponder key
malfunction.— B****
76 P1625 A OFF ECM Main Relay Switched
Off Too EarlyWhen ignition switch was
turned off, timing of the ECM
main relay turning off is too
early.No fail-safe function. No recovery. ECM malfunction.
3 /
58—
B OFF ECM Main Relay Switched
Off Too LateWhen ignition switch was
turned off, timing of the ECM
main relay turning off is too
late or does not off.No recovery. 1. ECM main relay
m a l f u n c t i o n .
2. ECM malfunction.3 /
58— Flash
CodeCodeSymptom
CodeMILDTC Name DTC Setting Condition Fail-Safe (Back Up) Recovery Condition Related Failure PartsRelated
ECM Pin
No.Related
Multiple
DTC4JA1-TC
(MT)4JH1-TC
(MT)4JH1-TC
(AT)

4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–129
Condition for setting the DTC and action taken when the DTC sets
Circuit Description
The mass air flow (MAF) sensor is part of the intake air
system. It is fitted between the air cleaner and
turbocharger and measure the mass air flowing into the
engine.
The mass air flow (MAF) sensor element measures the
partial air mass through a measurement duct on the
sensor housing.
The ECM monitors the MAF sensor supply voltage and
MAF sensor output voltage. The supply voltage is out of
range, DTC P0100 (Symptom Code 7) or P0100
(Symptom Code 9) will be stored. The output voltage
ex cessively high or low, DTC P0100 (Symptom Code B)
or P0100 (Symptom Code C) will be stored.
Diagnostic Aids
An intermittent may be caused by the following:
 Poor connections.
 Misrouted 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 for
damage. If the harness appears to be OK, observe
the “Mass Air Flow” display on the Tech2 while
moving connectors and wiring harness related to the
sensor.
Diagnostic Trouble Code (DTC) P0100 (Symptom Code 7) (Flash Code 65)
Mass Air Flow (MAF) Sensor Voltage Supply Circuit High Input
Flash
CodeCodeSymptom
CodeMIL DTC Name DTC Setting Condition Fail-Safe (Back Up)
65 P0100 7 ON Ma ss Air Flo w (MAF) Senso r
Voltage Supply Circuit High
InputMAF sensor power supply
voltage is more than 5.2V.ECM uses ma ss a ir flo w
1600mg/strk & EGR 10% co n-
ditions as substitute.
9 ON Mass Air Flow (MAF) Sensor
Voltage Supply Circuit Low
InputMAF sensor power supply
voltage is below 4.6V.
B ON Mass Air Flow (MAF) Sensor
Output Circuit Low Input1. Engine speed is between
600rpm and 5000rpm.
2. MAF se nsor o utput is
below -33.7mg/strk.
C ON Mass Air Flow (MAF) Sensor
Output Circuit High Input1. Engine speed is between
600rpm and 5000rpm.
2. MAF sensor output is more
tha n 1378mg/strk (4JA1-TC)
o r 1784mg/strk (4JH1-TC).
Step Action Value(s) Yes No
1Was 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 P0100 (Symptom Code 7) stored as
“Present Failure”?—Go to Step 3Refer to
Diagnostic Aids
and Go to Step
3

6E –130 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
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
clear the DTC information.
3. Operate the vehicle and monitor the “F0: Read
DTC Infor As Stored By ECU ” in the “F0:
Diagnostic Trouble Codes ”.
Was the DTC P0100 (Symptom Code 7) 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 MAF 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 Visually check the MAF sensor. Was the problem found? —Go to Step 11 Go to Step 6
6 Using the DVM and check the MAF sensor power supply circuit.
1. Ignition “On ”, engine “Off ”.
2. Disconnect the MAF & IAT 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 11 Less than 1V:
Go to Step 7
More than
specified value: Go to Step 8
7 Repair the open circuit between the ECM and MAF sensor.
Was the problem solved?
— Verify repair Go to Step 8
Step Action Value(s) Yes No
92
88 83
2 3
4
5
C-116
C-57(B)
V
4
C-116
83
4
C-116
C-57(B)

6E –132 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0100 (Symptom Code 9) (Flash Code 65)
Mass Air Flow (MAF) Sensor Voltage Supply Circuit Low Input
Step Action Value(s) Yes No
1Was 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 As Stored By ECU ” in
“ F0: Diagnostic Trouble Codes ”.
Is the DTC P0100 (Symptom Code 9) stored as
“ Present Failure ”? —Go to Step 3 Refer 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
clear the DTC information.
3. Operate the vehicle and monitor the “F0: Read
DTC Infor As Stored By ECU ” in the “F0:
Diagnostic Trouble Codes ”.
Was the DTC P0100 (Symptom Code 9) 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 MAF 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 Visually check the MAF sensor. Was the problem found? —Go to Step 10 Go to Step 6
6 Using the DVM and check the MAF sensor power supply circuit.
1. Ignition “On ”, engine “Off ”.
2. Disconnect the MAF & IAT sensor connector.
3. Check the circuit for short to ground circuit.
Was the DVM indicated specified value?
Approx imately 5.0V Go to Step 10Go to Step 7
92
88 83
2 3
4
5
C-116
C-57(B)
V
4
C-116

6E –134 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
Diagnostic Trouble Code (DTC) P0100 (Symptom Code B) (Flash Code 65)
Mass Air Flow (MAF) Sensor Output Circuit Low Input
Step Action Value(s) Yes No
1Was 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 As Stored By ECU ” in
“ F0: Diagnostic Trouble Codes ”.
Is the DTC P0100 (Symptom Code B) stored as
“ Present Failure ”? —Go to Step 3 Refer 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
clear the DTC information.
3. Operate the vehicle and monitor the “F0: Read
DTC Infor As Stored By ECU ” in the “F0:
Diagnostic Trouble Codes ”.
Was the DTC P0100 (Symptom Code B) 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 MAF 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 Visually check the MAF sensor. Was the problem found? —Go to Step 11 Go to Step 6
92
88 83
2 3
4
5
C-116
C-57(B)

4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E –137
Diagnostic Trouble Code (DTC) P0100 (Symptom Code C) (Flash Code 65)
Mass Air Flow (MAF) Sensor Output Circuit High Input
Step Action Value(s) Yes No
1Was 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 As Stored By ECU ” in
“ F0: Diagnostic Trouble Codes ”.
Is the DTC P0100 (Symptom Code C) stored as
“ Present Failure ”? —Go to Step 3 Refer 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
clear the DTC information.
3. Operate the vehicle and monitor the “F0: Read
DTC Infor As Stored By ECU ” in the “F0:
Diagnostic Trouble Codes ”.
Was the DTC P0100 (Symptom Code C) 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 MAF 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 Visually check the MAF sensor. Was the problem found? —Go to Step 11 Go to Step 6
92
88 83
2 3
4
5
C-116
C-57(B)