2004 ISUZU TF SERIES diagram

7A3-16 ON-VEHICLE SERVICE (AW30 –40LE)

Evaluation
i. If there is no 1 
2 upshift:

Solenoid S2 is stuck
 1 –2 shift valve is stuck
ii. If there is no 2 
3 upshift:

Solenoid S1 is stuck
 2 –3 shift valve is stuck
iii. If there is no 3 
OD upshift (throttle valve opening
1/2):

Solenoid S2 is stuck
 3 –OD shift valve is stuck
iv. If the shift point is defective: Refer to TROUBLESHOOTING CHART in this
section.
v. If the lock-up is defective: Refer to TROUBLESHOOTING CHART in this
section.
2. In the same manner, check the shock and slip at the 1 
2, 2 
3 and 3 
OD upshifts.
NOTE: Drive the vehicle on level ground.
Evaluation
If the shock is excessive:
Refer to TROUBLESHOOTING CHART in this section.
3. Run at “D" range lock-up or OD gear and check fo
r
abnormal noise and vibration.
NOTE: The check for the cause of abnormal noise and
vibration must be made with extreme care as it could
also be due to loss of balance in the propeller shaft,
differential, the torque converter, etc. or insufficient
bending, rigidity, etc. in the power train.



RUW37ASH000201

4. While running in “D" range, 2nd, 3rd gears and OD,
check to see that the possible kick-down vehicle
speed limits for 2 1, 3 1, 3 2, OD 3 and
OD 
2 kick-downs conform to those indicated on
the automatic shift diagram.



RUW37AMH000101
5. Check for abnormal shock and slip at kick-down.
6. While running in “D" range, OD gear or “lock-up",
shift to “2" and “L" ranges and check the engine
braking effect at each of these ranges.
7. Also check to see that downshift is made from 3 
2
or from OD to 3 and then to 2 immediately and that
2 
1 downshift point is within the limits shown in the
diagram when tested by releasing the accelerato
r
pedal and shifting into position of “L" while driving in
the third gear or in overdrive.

ON-VEHICLE SERVICE (AW30 –40LE) 7A3-17

Evaluation
i. If there is no engine braking effect in the “2" range:

Second coast (No.1) brake is defective.

ii. If there is no engine braking effect in the “L" range:

First and reverse (No.3) brake is defective.






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iii. Also check to see that downshift is made from 3 2
or from OD to 3 and then to 2 immediately and that
2 
1 downshift point is within the limits shown in the
diagram when tested by releasing the accelerato
r
pedal and shifting into “L" position while driving in
the third gear or in overdrive.



RUW37ASH000401

“ 2" Range Test
Shift into “2" range and, while driving with the
accelerator pedal held constantly at the specified point
(throttle valve opening 50% and 100%), push in one o
f
the pattern selectors (only for 4
4) and check on the
following points.
1.
At each of the above throttle openings, check to see
that the 1 
2 upshift takes place and that the shift
points conform to those shown on the automatic
shift diagram.
NOTE: There is no OD and no lock-up in the “2" range.


RTW46ASH000301

2. While running in the “2" range and 2nd gear,
release the accelerator pedal and check the
engine's braking effect.
3. Check for 2 
1 downshift and abnormal noise at
acceleration and deceleration, and for shock at
upshift and downshift.






RUW37ASH000501

7A3-18 ON-VEHICLE SERVICE (AW30 –40LE)

“ L" Range Test
1. While running above 80 km/h (50 mph) in the “D"
range, release your foot from the accelerator pedal
and shift into the “L" range.
Then check to see that the 2 
1 downshift occurs at
the specified point shown on the automatic shift
diagram.



RUW37ASH000601
2. While running in the “L" range, check to see that
there is no upshift to 2nd gear.
3. While running in the “L" range, release the
accelerator pedal and check the engine braking
effect.
4. Check for abnormal noise during acceleration and deceleration.







RUW37ASH000701

“ R" Range Test
Shift into the “R" range and, while starting at full throttle,
check for slipping.




RUW37ASH000801
“ P" Range Test
Stop the vehicle on a grade (more than 9%) and afte
r
shifting into the “P" range, release the parking brake.
Then check to see that the parking lock pawl holds the
vehicle in place.

7A1-2 CONSTRUCTION AND FUNCTION

PAGE
LOCK-UP CONTROL ..............................................................................................................7A1- 30
DIRECT ELECTRIC SHIFT CONTROL (DESC) ................................................................7A1- 31
LEARNING CONTROL ............................................................................................... 7A1- 33
MAJOR INPUT/OUTPUT COMPONENT AND THEIR FUNCTIONS .......................... 7A1- 34
CONTROL CIRCUIT BLOCK DIAGRAM .................................................................... 7A1- 35
GEAR TRAIN (TRANSMISSION MECHANISM) OPERATION AND
HYDRAULIC CIRCUIT ................................................................................................. 7A1- 36
CONSTRUCTION AND OPERATION ......................................................................... 7A1- 36
COMPONENT NAME AND FUNCTION ...................................................................... 7A1- 36
COMPONENT AND THEIR OPERATING CONDITION ............................................. 7A1- 37

CONSTRUCTION AND FUNCTION 7A1-27
Item Description
- 4L mode -
4L mode setting condition
4L switch: On
Vehicle speed: More than 5km/h
Above conditions are met at the same time.
4L mode reset condition
4L switch: Off
Vehicle speed: Less than 4km/h
Above conditions are met at the same time.

- Down slope mode -
Down slope mode setting condition
Brake switch: On
Engine idle condition: More than 2.5 seconds
Select lever position: D or 3 range
Vehicle speed: More than 55km/h
Vehicle speed change: More than 1km/h
Above conditions are met at the same time.
Down slope mode reset condition
Engine idle condition: Not idle condition
Select lever position: Other than D or 3 range
At least, one of above conditions is met.

- Power Mode -
When power drive switch is On at only D range or 3 range, the shift change is performed by
1 – 4 speed based on shift diagram set as power pattern.

- Up slope mode -
Up-slope reasoning value is calculated from the average throttle angle and the average
acceleration. Otherwise, up-slope reasoning value is calculated from the vehicle speed.
TCM judges as up-slope mode when the former is bigger than latter.


Lock-up control The lock-up solenoid adjusts the pressure based on the signal from the TCM according to
the vehicle speed, throttle opening and other input signals based on the pre-set lock-up
point to control the lock-up.
Smooth lock-up control engages and disengages the clutch smoothly at the time of lock-up.
When the oil temperature is low (below 20
C) or high (above 128
C), lock-up is prohibited
even when the vehicle is at a lock-up speed.
The lock-up is disengaged also when the throttle is closed.
Direct electronic shift
control (DESC)
The duty cycle type solenoid is used for each clutch and brake. The solenoid adjusts the
clutch pressure to be suited to the engine load and vehicle traveling condition based on the
signal from the TCM. The pressure switch provided in the control valve oil passage sends
the oil pressure condition to the TCM to control the disengagement and engagement of the
clutch and brake directly and finely.
Learning control Learning is controlled to correct the oil pressure control timing to engage or disengage the
clutch optimally in order to compensate changes of the engine performance and changes
of the transmission with time. It is controlled to bring the speed-change time closer to the
value pre-set to the TCM.

CONSTRUCTION AND FUNCTION 7A1-35
CONTROL CIRCUIT BLOCK DIAGRAM



Speed sensor
Turbine sensor
Brake switch
Inhibitor switch
Power drive, 3rd start
switch
ATF oil thermo sensor
High clutch oil pressure
switch
2-4 brake oil pressure
switch
Low & reverse brake oil
pressure switch
Transfer control module
(4WD Only)



Engine Control Module
(ECM)
Line pressure solenoid
Low clutch solenoid
High clutch solenoid
2-4 brake solenoid
Low & reverse brake
solenoid
Lock-up solenoid
ATF temperature
indicator lamp
Speed meter (2WD
Only)
Power, 3rd start indicator
lamp
Check trans indicator
lamp
Data link connector Self-diagnosis
function



Transmission
Control
Module
(TCM)
4L mode
Engine
speed
Throttle
angle
Figure 54. Control Circuit Block Diagram

DIAGNOSIS (JR405E) 7A2-1
SECTION 7A2
DIAGNOSIS
TABLE OF CONTENTS
PAGE
BASIC TROUBLE SHOOTING..................................................................................................7A2-6
CHECK TRANS INDICATOR & SELF DIAGNOSIS..............................................................7A2-7
DIAGNOSIS WITH TECH 2........................................................................................................7A2-9
TECH 2 CONNECTION .................................................................................................. 7A2-9
TECH 2 OPERATING FLOW CHART (START UP)..............................................................7A2-10
TYPICAL SCAN DATA................................................................................................................7A2-13
MISCELLANEOUS TEST...........................................................................................................7A2-14
INTERMITTENT DIAGNOSIS....................................................................................................7A2-16
SNAPSHOT DISPLAY WITH TIS 2000....................................................................................7A2-17
SERVICE PROGRAMMING SYSTEM (SPS) ................................................................. 7A2-21
CIRCUIT DIAGRAM.....................................................................................................................7A2-24
PART LOCATION........................................................................................................................7A2-26
CONNECTOR LIST.....................................................................................................................7A2-31
DIAGNOSIS TROUBLE CODE TABLE...................................................................................7A2-33
FAIL-SAFE FUNCTION..............................................................................................................7A2-35
DTC P0722 (FLASH CODE 11) VEHICLE SPEED SENSOR NO SIGNAL......................7A2-36
DTC P0727 (FLASH CODE 13) ENGINE REVOLUTION SENSOR NO SIGNAL............7A2-38
DTC P0717 (FLASH CODE 14) TURBINE SPEED SENSOR NO SIGNAL......................7A2-40
DTC P0710 (FLASH CODE 15) ATF TEMPERATURE SENSOR FAILURE....................7A2-42
DTC P0560 (FLASH CODE 16) SYSTEM VOLTAGE FAILURE........................................7A2-43
DTC P0705 (FLASH CODE 17) INHIBITOR SWITCH FAILURE........................................7A2-44
DTC P1120 (FLASH CODE 22) THROTTLE SIGNAL FAILURE........................................7A2-46
DTC P1875 (FLASH CODE 25) GND RETURN CIRCUIT FAILURE.................................7A2-47
DTC P0753 (FLASH CODE 31) LOW & REVERSE BRAKE DUTY
SOLENOID FAILURE................................................................................................................7A2-48
DTC P0758 (FLASH CODE 32) 2-4 BRAKE DUTY SOLENOID FAILURE......................7A2-51
DTC P0763 (FLASH CODE 33) HIGH CLUTCH DUTY SOLENOID FAILURE................7A2-54
DTC P0768 (FLASH CODE 34) LOW CLUTCH DUTY SOLENOID FAILURE................7A2-57

DIAGNOSIS (JR405E) 7A2-5
PAGE
NO. Z3: MODE LAMP (POWER DRIVE OR 3RD START) LIGHTS UP WHEN
THE POWER MODE OR 3RD START MODE IS TURNED OFF .................................. 7A2-137
NO. Z4: OIL TEMPERATURE WARNING LAMP LIGHTS UP ...................................... 7A2-137
NO. Z5: SELECT LEVER FEELING IS FAULTY. .......................................................... 7A2-137
NO. Z6: POOR FUEL CONSUMPTION ......................................................................... 7A2-138
NO. Z7: PATTERN SELECT SWITCH IS FAULTY........................................................ 7A2-138
NO. Z8: OIL IS SPLASHED DURING THE RUNNING .................................................. 7A2-138
NO. Z9: ABNORMAL SMELL ........................................................................................ 7A2-138
NO. Z10: ATF QUANTITY IS LOW OR HIGH ................................................................ 7A2-138
NO. Z11: ABNORMAL OIL PRESSURE........................................................................ 7A2-139
NO. Z12: REVERSE BUZZER DOES NOT RING .......................................................... 7A2-139
STALL TEST .................................................................................................................. 7A2-140
LINE PRESSURE TEST................................................................................................. 7A2-141
TIME LAG TEST............................................................................................................. 7A2-143
TEST DRIVE................................................................................................................... 7A2-144
SHIFT POINT CHART .................................................................................................... 7A2-147
SHIFT POINT DIAGRAM................................................................................................ 7A2-149
TCM VOLTAGE CHECK ................................................................................................ 7A2-154