ignition ISUZU TF SERIES 2004 Workshop Manual
[x] Cancel search | Manufacturer: ISUZU, Model Year: 2004, Model line: TF SERIES, Model: ISUZU TF SERIES 2004Pages: 4264, PDF Size: 72.63 MB
Page 1087 of 4264

ELECTRICAL-BODY AND CHASSIS 8A-429
No. Connector face No. Connector face
E-23
(4JH1-TC)
Gray TPS 2 main E-44
Gray Vehicle speed sensor
E-24
~
E-29 NOT USED E-45
(4JH1-TC)
Gray 2WD-4WD switch
E-30
(4JH1-TC)
Gray A/T speed sensor E-46
(4JH1-TC)
BrownH-L neutral switch
E-31
(4JH1-TC)
Gray Turbine sensor E-47
~
E-48 NOT USED
E-32
~
E-34 NOT USED E-49
(4JH1-TC)
Glow plug
E-35
(4JH1-TC)
(C24SE)
Black Motor actuator E-50
NOT USED
E-36
~
E-40 NOT USED E-51
(6VE1)
Fuel injector
E-41
(4JH1-TC)
Black Coolant temp sensor E-51
(4JH1-TC)
BlackInhibiter switch
E-42
Natural
green
Backup lamp switch E-52
(6VE1)
Fuel injector
E-43
Natural
green
Backup lamp switch E-53
(6VE1)
Ignition coil
Page 1088 of 4264

8A-430 ELECTRICAL-BODY AND CHASSIS
No. Connector face No. Connector face
E-54
(6VE1)
Ignition coil E-62
(6VE1)
Cam position sensor
E-54
(4JH1-TC)
Black A/T term ASM E-64
(C24SE)
(6VE1)
Oil pressure switch (P/STRG)
E-55
(6VE1)
Ignition coil E-65
(C24SE)
(6VE1)
Thermo unit
E-56
(6VE1)
Ignition coil E-66
(C24SE)
(6VE1)
Duty solenoid
E-57
(6VE1)
Ignition coil E-67
NOT USED
E-58
(6VE1)
Ignition coil E-68
(C24SE)
Throttle position sensor
E-59
(C24SE)
(6VE1)
(6VE1) Crank position sensor (C24SE) E-68
(6VE1)
Throttle position sensor
E-60
(C24SE)
ECM E-69
(6VE1)
Temperature sensor
E-60
(6VE1)
ECM-A E-70
(C24SE)
IACV
E-61
(6VE1)
ECM-B E-70
(6VE1)
IACV
Page 1108 of 4264

8B-10 CRUISE CONTROL SYSTEM
Diagnosis
The cruise control unit uses the cruise main indicator light and diagnosis the failure, when the control unit detects
abnormality on the table below.
PART POSSIBLE CAUSE DETECTION PERIOD DTC
Actuator Motor system short circuit Energizing motor 1-1
Clutch system short circuit Energizing clutch 1-2
Clutch system open circuit Energizing clutch 1-2
Mechanical defect Cruise controlling 1-3
Close side of motor system open circuit Cruise controlling 1-1
Cruise control unit Close side of motor system open circuit While starter sw on 1-4
Clutch output abnormality While starter sw on 1-4
Vehicle speed sensor Signal of vehicle speed disconnection Cruise controlling 2-1
Signal of vehicle speed abnormality Cruise controlling 2-1
Switch Turning on switch at all times While starter sw on 3-1
Turning on switch at the same time While starter sw on 3-1
DTC : Diagnostic Trouble Code
DTC Display Condition
1. With the vehicle stationary and the ignition ON, activate the ‘Cruise Cancel’ switch three times within 2 seconds.
2. If there are no DTC’s stored in the Cruise control unit, the LED on the Cruise Main switch will blink rapidly (2Hz).
3. Any DTC’s stored in the Cruise control unit will be displayed by the CRUISE SET warning lamp in the meter
cluster.
4. Read the set DTC’s by referring to then charts on this page.
NOTE:
The DTC display mode will be aborted if either the vehicle speed rises above 10km/h or the RESUME switch is
operated.
The control module stores the DTC in a ‘volatile’ memory – that is the memory is only active while the ignition is
ON.
Turning the ignition to the OFF position will clesr any stored DTC’s.
Page 1166 of 4264

6A – 26 ENGINE MECHANICAL
041RY00011
Draining Procedure
The indicator light will come on when the water level in the
water separator exceeds the specified level.
Drain the water and foreign material from the water
separator (inside chassis frame) with the following
procedure.
1. Place the drain pan under the drain plug.
2. Loosen the drain plug and drain water.
3. After draining the water, tighten the drain plug.
4. Operate the priming pump on the fuel filter several
times and check for fuel leakage.
5. Check the water separator indicator light. It should be
off.
Except EURO III model
RTW46ASH002901
For EURO III model
RTW46ASH000501
Air Bleeding
1. Operate the priming pump until strong resistance is
felt.
2. Wait 1 minute, and operate the priming pump until
strong resistance is felt.
3. Once more wait, and operate the priming pump until
strong resistance is felt.
4. Turn the ignition switch to the "ON" position. Wait until
the glow indicator lamp turns off.
5. Turn the ignition switch to the "START" position and
crank the engine until it starts.
6. If the engine does not start, repeat Step 3 - 5.
7. Allow the engine to idle for 3 minutes to bleed air
completely form the fuel system and check for fuel
leakage.
Note:
Insufficient air bleeding may cause the Diagnostic
Trouble Code (DTC) store or improper engine
performance.
Page 1377 of 4264

4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–5
DIAGNOSTIC TROUBLE CODE (DTC) P0400
(SYMPTOM CODE 8) (FLASH CODE 32)
EXHAUST GAS RECIRCULATION CIRCUIT
SHORT TO BATTERY ............................ 6E-227
Circuit Description ..................................... 6E-228
Diagnostic Aids .......................................... 6E-228
Diagnostic Trouble Code (DTC) P0400
(Symptom Code 3) (Flash Code 32) Ex haust
Gas Recirculation Flow Ex cessive Detected 6E-228
Diagnostic Trouble Code (DTC) P0400
(Symptom Code 4) (Flash Code 32) Ex haust
Gas Recirculation Circuit Short to Ground or
Open Circuit ............................................. 6E-232
Diagnostic Trouble Code (DTC) P0400
(Symptom Code 5) (Flash Code 32) Ex haust
Gas Recirculation Flow Insufficient Detected 6E-235
Diagnostic Trouble Code (DTC) P0400
(Symptom Code 8) (Flash Code 32) Ex haust
Gas Recirculation Circuit Short to Battery 6E-238
DIAGNOSTIC TROUBLE CODE (DTC) P0500
(SYMPTOM CODE 1) (FLASH CODE 24)
VEHICLE SPEED SENSOR CIRCUIT HIGH
INPUT ...................................................... 6E-240
DIAGNOSTIC TROUBLE CODE (DTC) P0500
(SYMPTOM CODE A) (FLASH CODE 24)
VEHICLE SPEED SENSOR INPUT SIGNAL
FREQUENCY TOO HIGH ....................... 6E-240
DIAGNOSTIC TROUBLE CODE (DTC) P0500
(SYMPTOM CODE B) (FLASH CODE 24)
VEHICLE SPEED SENSOR INCORRECT
SIGNAL ................................................... 6E-240
Circuit Description ..................................... 6E-241
Diagnostic Aids .......................................... 6E-241
Diagnostic Trouble Code (DTC) P0500
(Symptom Code 1) (Flash Code 24) Vehicle
Speed Sensor Circuit High Input ............. 6E-241
Diagnostic Trouble Code (DTC) P0500
(Symptom Code A) (Flash Code 24)
Vehicle Speed Sensor Input Signal
Frequency Too High ................................ 6E-245
Diagnostic Trouble Code (DTC) P0500
(Symptom Code B) (Flash Code 24)
VehicleSpeed Sensor Incorrect Signal .... 6E-248
DIAGNOSTIC TROUBLE CODE (DTC) P0560
(SYMPTOM CODE 1) (FLASH CODE 35)
SYSTEM VOLTAGE TOO HIGH ............. 6E-253
DIAGNOSTIC TROUBLE CODE (DTC) P0560
(SYMPTOM CODE 2) (FLASH CODE 35)
SYSTEM VOLTAGE TOO LOW .............. 6E-253
DIAGNOSTIC TROUBLE CODE (DTC) P0560
(SYMPTOM CODE A) (FLASH CODE 35)
SYSTEM VOLTAGE MALFUNCTION ..... 6E-253
Circuit Description ..................................... 6E-253Diagnostic Aids .......................................... 6E-254
Diagnostic Trouble Code (DTC) P0560
(Symptom Code 1) (Flash Code 35)
System Voltage Too High ........................ 6E-254
Diagnostic Trouble Code (DTC) P0560
(Symptom Code 2) (Flash Code 35)
System Voltage Too Low ......................... 6E-256
Diagnostic Trouble Code (DTC) P0560
(Symptom Code A) (Flash Code 35)
System Voltage Malfunction .................... 6E-258
DIAGNOSTIC TROUBLE CODE (DTC) P0561
(SYMPTOM CODE A) (FLASH CODE 18)
IGNITION SWITCH CIRCUIT
MALFUNCTION ....................................... 6E-260
DIAGNOSTIC TROUBLE CODE (DTC) P0561
(SYMPTOM CODE B) (FLASH CODE 18)
IGNITION SWITCH CIRCUIT
MALFUNCTION ....................................... 6E-260
Circuit Description ...................................... 6E-261
Diagnostic Aids .......................................... 6E-261
Diagnostic Trouble Code (DTC) P0561
(Symptom Code A) (Flash Code 18)
Ignition Switch Circuit Malfunction ........... 6E-261
Diagnostic Trouble Code (DTC) P0561
(Symptom Code B) (Flash Code 18)
Ignition Switch Circuit Malfunction ........... 6E-261
DIAGNOSTIC TROUBLE CODE (DTC) P0602
CONTROL MODULE PROGRAMMING
ERROR .................................................... 6E-264
Circuit Description & Diagnostic Aids ........ 6E-264
Diagnostic Trouble Code (DTC) P0602
Control Module Programming Error ......... 6E-264
DIAGNOSTIC TROUBLE CODE (DTC) P0606
(SYMPTOM CODE A) (FLASH CODE 28)
ECU MALFUNCTION .............................. 6E-265
DIAGNOSTIC TROUBLE CODE (DTC) P0606
(SYMPTOM CODE B) (FLASH CODE 28)
ECU MALFUNCTION .............................. 6E-265
Circuit Description & Diagnostic Aids ........ 6E-265
Diagnostic Trouble Code (DTC) P0606
(Symptom Code A) (Flash Code 28)
ECU Malfunction ...................................... 6E-265
Diagnostic Trouble Code (DTC) P0606
(Symptom Code B) (Flash Code 28)
ECU Malfunction ...................................... 6E-267
DIAGNOSTIC TROUBLE CODE (DTC) P0645
(SYMPTOM CODE 4) (FLASH CODE 46)
A/C COMPRESSOR RELAY CIRCUIT
VOLTAGE LOW ...................................... 6E-268
DIAGNOSTIC TROUBLE CODE (DTC) P0645
(SYMPTOM CODE 8) (FLASH CODE 46)
A/C COMPRESSOR RELAY CIRCUIT
VOLTAGE HIGH ...................................... 6E-268
Page 1381 of 4264

4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–9
ABBREVIATION CHARTS
A bbreviations A ppellation
A/C Air conditioner
A/T Automatic transmission
ACC Accessory
BLK Black
BLU Blue
BRN Brown
CAN Controller Area Network
CEL Check engine lamp
CKP Crankshaft position sensor
DLC Data link connector
DTC Diagnosis trouble code
DVM Digital voltage meter
ECM Engine control module
ECT Engine coolant temperature
EEPROM Electrically erasable & programmable read only memory
EGR Ex haust gas recirculation
EVRV Electric vacuum regulating valve
GND Ground
GRY Gray
IAT Intake air temperature
IG Ignition
M/T Manual transmission
MAB High pressure solenoid valve cutoff (German abbreviation)
MAF Mass air flow
MIL Malfunction indicator lamp
OBD On-board diagnostic
ORN Orange
PNK Pink
RED Red
PSG Pump control unit (German abbreviation)
SW Switch
TCM Transmission control module
TCV Timing control valve
TDC Top dead center
TPS Throttle position sensor
VCC Voltage constunt control
VIO Violet
VSS Vehicle speed sensor
WHT Whi te
YEL Yellow
Page 1412 of 4264

6E–40 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
CONNECTOR LIST
No. Connector face No. Connector face
B-24
Green Meter-BC-56
ECM-A
B-54
White J/B I2C-57
ECM-B
B-56
White J/B I4C-77
Clutch switch
B-58
Black Check connectorC-94
White TCM
B-62
White Ignition switch (IGSUB : G1)C-95
White TCM
B-63
White Ignition switch (IGSUB : G2)C-107
White J/B E2
B-68
ImmobilizerC-108
White J/B E1
C-2
Silver Engine room-RH groundC-109
Silver Body-LH ; ground
C-36
Silver Engine room-LH ; GroundC-115
Brown EVRV
C-44
White Stop lamp switchC-116
Page 1454 of 4264

6E–82 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
GENERAL SERVICE INFORMATION
Serviceability Issues
Non-OEM Parts
All of the OBD diagnostics have been calibrated to run
with OEM parts. Accordingly, if commercially sold
sensor or switch is installed, it makes a wrong diagnosis
and turns on the check engine lamp.
Aftermarket electronics, such as cellular phones,
stereos, and anti-theft devices, may radiate EMI into the
control system if they are improperly installed. This may
cause a false sensor reading and turn on the check
engine lamp.
Poor Vehicle Maintenance
The sensitivity of OBD diagnostics will cause the check
engine lamp to turn on if the vehicle is not maintained
properly. Restricted oil filters, fuel filters, and crankcase
deposits due to lack of oil changes or improper oil
viscosity can trigger actual vehicle faults that were not
previously monitored prior to OBD. Poor vehicle
maintenance can not be classified as a “non-vehicle
fault”, but with the sensitivity of OBD diagnostics,
vehicle maintenance schedules must be more closely
followed.
Related System Faults
Many of the OBD system diagnostics will not run if the
ECM detects a fault on a related system or component.
Visual/Physical Engine Compartment
Inspection
Perform a careful visual and physical engine
compartment inspection when performing any
diagnostic procedure or diagnosing the cause of an
emission test failure. This can often lead to repairing a
problem without further steps. Use the following
guidelines when performing a visual/physical
inspection:
Inspect all vacuum hoses for punches, cuts,
disconnects, and correct routing.
Inspect hoses that are difficult to see behind other
components.
Inspect all wires in the engine compartment for
proper connections, burned or chafed spots, pinched
wires, contact with sharp edges or contact with hot
exhaust manifolds or pipes.
Basic Knowledge of Tools Required
NOTE: Lack of basic knowledge of this powertrain
when performing diagnostic procedures could result in
an incorrect diagnosis or damage to powertrain
components. Do not attempt to diagnose a powertrain
problem without this basic knowledge.
A basic understanding of hand tools is necessary to
effectively use this section of the Service Manual.
ON-BOARD DIAGNOSTIC (OBD)
On-Board Diagnostic (Self Diagnosis
System) Tests
A diagnostic test is a series of steps, the result of which
is a pass or fail reported to the diagnostic ex ecutive.
When a diagnostic test reports a pass result, the
diagnostic ex ecutive records the following data:
The diagnostic test has been completed since the
last ignition cycle.
The diagnostic test has passed during the current
ignition cycle.
The fault identified by the diagnostic test is not
currently active.
When a diagnostic test reports a fail result, the
diagnostic ex ecutive records the following data:
The diagnostic test has been completed since the
last ignition cycle.
The fault identified by the diagnostic test is currently
active.
The fault has been active during this ignition cycle.
The operating conditions at the time of the failure.
The Diagnostic Executive
The Diagnostic Executive is a unique segment of
software which is designed to coordinate and prioritize
the diagnostic procedures as well as define the protocol
for recording and displaying their results. The main
responsibilities of the Diagnostic Ex ecutive are listed as
follow s:
Commanding the check engine lamp on and off
DTC logging and clearing
Current status information on each diagnostic
Diagnostic Information
The diagnostic charts and functional checks are
designed to locate a faulty circuit or component through
a process of logical decisions. The charts are prepared
with the requirement that the vehicle functioned
correctly at the time of assembly and that there are not
multiple faults present.
There is a continuous self-diagnosis on certain control
functions. This diagnostic capability is complemented
by the diagnostic procedures contained in this manual.
The language of communicating the source of the
malfunction is a system of diagnostic trouble codes.
When a malfunction is detected by the control module, a
diagnostic trouble code is set and the check engine
lamp is illuminated.
Check Engine Lamp
The check engine lamp looks the same as the check
engine lamp you are already familiar with, the “Check
Engine” lamp.
Basically, the check engine lamp is turned on when the
Page 1455 of 4264

4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS 6E–83
ECM detects a DTC that will impact the vehicle
emissions.
When the check engine lamp remains “ON” while the
engine is running, or when a malfunction is
suspected due to a driveability or emissions problem,
a Powertrain On-Board Diagnostic (OBD) System
Check must be performed. The procedures for these
checks are given in On-Board Diagnostic (OBD)
System Check. These checks will ex pose faults
which may not be detected if other diagnostics are
performed first.
Data Link Connector (DLC)
The provision for communication with the contorl
module is the Data Link Connector (DLC). It is located
behind the lower front instrument panel. The DLC is
used to connect to a Tech 2. Some common uses of the
Tech 2 are listed below:
Identifying stored Diagnostic Trouble Codes (DTCs).
Clearing DTCs.
Reading serial data.
Verifying Vehicle Repair
Verification of vehicle repair will be more
comprehensive for vehicles with OBD system
diagnostic. Following a repair, the technician should
perform the following steps:
1. Review and record the Fail Records for the DTC
which has been diagnosed.
2. Clear DTC(s).
3. Operate the vehicle within conditions noted in the
Fail Records.
4. Monitor the DTC status information for the specific
DTC which has been diagnosed until the diagnostic
test associated with that DTC runs.
Following these steps is very important in verifying
repairs on OBD systems. Failure to follow these steps
could result in unnecessary repairs.
Reading Flash Diagnostic Trouble Codes
The provision for communicating with the Engine
Control Module (ECM) is the Data Link Connector
(DLC). The DLC is located in the front console box . It is
used in the assembly plant to receive information in
checking that the engine is operating properly before it
leaves the plant.
The diagnostic trouble code(s) (DTCs) stored in the
ECM’s memory can be read either through a hand-held
diagnostic scanner plugged into the DLC or by counting
the number of flashes of the check engine lamp when
the diagnostic test terminal of the DLC is grounded. The
DLC terminal “6” (diagnostic request) is pulled “Low”
(grounded) by jumping to DLC terminal “4 or 5”, which is
a ground wire.
This will signal the ECM that you want to “flash” DTC(s),
if any are present. Once terminals “4 or 5” and “6” have
been connected, the ignition switch must be moved to
the “ON” position, with the engine not running.
The check engine lamp will indicate a DTC three times if
a DTC is present. If more than one DTC has been
stored in the ECM’s memory, the DTC(s) will be output
from the lowest to the highest, with each DTC being
displayed three times.
The DTC display will continue as long as the DLC is
shorted.
Reading Diagnostic Trouble Codes Using a
Tech 2
The procedure for reading diagnostic trouble code(s) is
to used a diagnostic Tech 2. When reading DTC(s),
follow instructions supplied by Tech 2 manufacturer.
For the 1998 model year, Isuzu dealer service
departments will continue to use Tech 2.
Clearing Diagnostic Trouble Codes
To clear Diagnostic Trouble Codes (DTCs), use the
Te c h 2 “clear DTCs” or “clear information” function.
When clearing DTCs follow instructions supplied by the
Tech 2 manufacturer.
History DTC
History DTC can be candeled after 40 cycle driving with
no defect. Or history code can be deleted by Tech 2
“Clear DTCs” function.
Page 1460 of 4264

6E–88 4JA1/4JH1 ENGINE DRIVEABILITY AND EMISSIONS
TYPICAL SCAN DATA & DEFINITIONS (ENGINE DATA)
4JA 1-TC ENGINE
Use the typical values table only after the On-Board Diagnostic System check has been completed, no DTC(s) were
noted, and you have determined that the On-Board Diagnostic are functioning properly.
Tech2 values from a properly running engine may be used for comparison with the engine you are diagnosing.
Condition : Vehicle stopping, engine running, air conditioning off & after warm-up (Coolant temperature approx imately
80 deg. C)
Tech 2 Parameter Units Idle 1500rpm 2000rpm Description
1 Engine Speed rpm 730 1475 -
15251975 -
2025The engine speed is measured by ECM from the CKP
se nso r.
2 Vehicle Speed km/h / MPH 0 0 0 This displays vehicle speed. The vehicle speed is
measured by ECM from the vehicle speed sensor.
3 Pump Spe ed rpm 345 - 385 725 - 775 975 - 1025 This displa ys injectio n pump spe ed. The inje ction spe ed is
measured by ECM from the pump cam sensor.
4 Accelerator Position
Sensor Signal% 0 4 - 6 6 - 8 Throttle position operating angle is measured by the ECM
fro m throttle po sition o utput v olta ge . This sho uld display
0% a t idle a nd 99 - 100% a t full thro ttle .
5 Idle Switch Activ e /
Inactive 0VActive Active Inactive 0V This displays operating status of the idle switch. This
should display "Active" until the accelerator position nearly
4 - 5%.
6 Mass Air Flow
Sensormg/strk 380 - 420 360 - 400 380 - 420 This displays calculated intake air volume for one cylinder
stroke. The mass air flow is measured by ECM from the
MAF sensor output voltage.
7 Desire d Ma ss Air
Flo wmg/strk 350 350 350 - 370 This displays desired intake air volume for one cylinder
stroke. The desired mass air flow is calculated by ECM
de pe nding on engine conditio n.
8 Baro metric Pre ssure hpa De pe nds
on altitudeDe pe nds
o n a ltitudeDe pe nds
on altitudeThe ba rome tric pre ssure is mea sure d by ECM from the
sensor in the ECM. This data is changing by altitude.
9 Desired Injection
Qua ntitymg/stk 8 - 10 6 - 10 7 - 10 This displays desired value from the ECM. The ECM
co mpe nsates fo r fue l ra te to ba sic ra te.
10 Injection Qua ntity mg/stk 8 - 10 5 - 10 5 - 9 This displa y s ca lculated a ctua l fue l qua ntity from the PSG.
The PSG receives desired injection quantity from the ECM.
And, it compensates actual injection depending on timer
po sitio n to de termine duration o f the high pre ssure
solenoid valve operation.
11 Desire d Fuel Injection
St a r tde g. CA 2 - 4 2- 5 3 - 5 This display s de sired injection timing from the ECM. The
ECM compensates for fuel injection timing by throttle
position and various sensor signal.
12 Actua l Injectio n Sta rt de g. CA 2 - 4 2 - 5 3 - 5 This display s ca lculate d a ctua l inje ctio n timing ba se d o n
CKP signa l a nd pump ca m signal. The PSG controls TCV
duty ra tio to mee t desired inje ctio n timing from the ECM.
13 Coolant Temperature deg. C / deg.
F80 - 85 80 - 85 80 - 85 The ECT is measured by ECM from ECT sensor output
voltage. This data is changing by coolant temperature.
When the engine is normally warm upped, this data
displays approximately 80 deg. C.
14 Fuel Temperature deg. C / deg.
FDe pe nds
on fuel
temp.De pe nds
on fuel
te mp.De pe nds
on fuel
te mp.The FT is measured by PSG from FT sensor. This data is
changing by fuel temperature.
15 Inta ke Air
Temperaturedeg. C / deg.
FDe pe nds
on ambient
temp.De pe nds
on ambient
te mp.De pe nds
on ambient
te mp.The IAT is measured by ECM from IAT sensor output
voltage. This data is changing by intake air temperature.
16 Ignition Status On12V/
Off0VOn 12V On 12V On 12V This displays the key switch status indicated by the ECM
with key switch signal. This should display "Off 0V" at key
OFF and "On12V" at key ON.
17 Brake Switch 1 Active/
InactiveInactive Inactive Inactive This displays operating status of the brake switch. This
should display "Active" when the brake pedal is stepped
on.