content ISUZU TF SERIES 2004 Manual Online

CONSTRUCTION AND FUNCTION 7A1-1

SECTION 7A1
CONSTRUCTION AND FUNCTION
TABLE OF CONTENTS
PAGE
DESCRIPTION ..............................................................................................................................7A1- 3
CONSTRUCTION ....................................................................................................................7A1- 3
MAIN DATA AND SPECIFICATION .....................................................................................7A1- 4
NUMBER PLATE LOCATION ...............................................................................................7A1- 5
ELECTRONIC CONTROL COMPONENTS LOCATION ..................................................7A1- 6
TRANSMISSION CONTROL UNIT (TCM) PERIPHERAL CIRCUIT ..............................7A1- 7
STRUCTURE AND FUNCTION OF COMPONENT ...........................................................7A1- 8
TORQUE CONVERTER (WITH LOCK-UP FUNCTION) ..................................................7A1- 8
OIL PUMP .................................................................................................................................7A1- 9
INPUT SHAFT ..........................................................................................................................7A1- 10
OUTPUT SHAFT ......................................................................................................................7A1- 10
GEAR SHIFTING MECHANISM ............................................................................................7A1- 10
CONTROL VALVE ...................................................................................................................7A1- 14
OIL PASSAGE .........................................................................................................................7A1- 19
PARKING FUNCTION .............................................................................................................7A1- 20
INHIBITOR SWITCH ...............................................................................................................7A1- 21
TURBINE SENSOR .................................................................................................................7A1- 22
SPEED SENSOR .....................................................................................................................7A1- 22
THROTTLE POSITION SENSOR (TPS) .............................................................................7A1- 23
ENGINE SPEED SENSOR (=TDC SENSOR) ....................................................................7A1- 23
BRAKE SWITCH ......................................................................................................................7A1- 24
MODE SELECT SWITCH .......................................................................................................7A1- 24
TRANSMISSION CONTROL MODULE (TCM) ..................................................................7A1- 25
CONTROL MECHANISM ............................................................................................................7A1- 26
CONTENT OF FUNCTION AND CONTROL ......................................................................7A1- 26
CONTROL ITEM, INPUT AND OUTPUT .................................................................... 7A1- 29
LINE PRESSURE CONTROL ..................................................................................... 7A1- 30

7A1-26 CONSTRUCTION AND FUNCTION
CONTROL MECHANISM
CONTENT OF FUNCTION AND CONTROL
Item Description
Line pressure control TCM issues a signal according to the vehicle traveling, engine load and other conditions to
TCM and the ON/OFF type line pressure solenoid is driven to switch the line pressure to
high or low pressure.
The line pressure solenoid is switched to the low pressure side when the solenoid is turned
ON (power supplied) and to the high pressure side when turned OFF (no power supplied).
In the forward travel range (D, 3, 2, L range), the line pressure decreases lower than that in
the P, N, and R range through the oil pressure circuit for the forward travel range.


Gear shift control The TCM issues a shift solenoid drive signal based on the traveling mode switch, inhibitor
switch, vehicle speed, throttle opening and other input signal to control the optimum gear
position automatically.
Speed change features have been set up to the TCM; the normal mode is suited to usual
traveling and the power mode is appropriate when the vehicle is loaded or accelerates the
speed.
In addition, speed change features used only for high oil temperature, hill climbing, and
down have been set up to the TCM, which are automatically switched depending on the
traveling conditions.
When the oil temperature is low (below 10
C), speed change from the third to the fourth
speed is prohibited by the gear shift control.


Shift pattern selection
control
According to a vehicle condition, the TCM selects the following shift pattern.

Selection Priority Shift Pattern 3rd Start Lamp Power Drive Lamp
High High Temperature OFF OFF
3rd Start ON
4L
Power SW Off
OFF
Down Slop Power SW On
Power ON
Up Slope
Low Normal
OFF
OFF

- High temperature mode -
High temperature mode setting condition
ATF temperature: More than 123
C
Above condition is met for more than 10 seconds.
High temperature mode cancel condition
ATF temperature: Less than 116
C
Above condition is met for more than 10 seconds.

- 3rd start mode -
3rd start mode setting condition
3rd start switch: On  Off (Pushed)
Vehicle speed: Less than 11km/h
ATF temperature: Less than 115
C
Throttle position: Less than 8%
Select lever position: D range
Above conditions are met at the same time.
3rd start mode reset condition
3rd start switch: On  Off again(Pushed again)
Vehicle speed: More than 34km/h
Select lever position: Other than D range
At least, one of above conditions is met.

CONSTRUCTION AND FUNCTION 7A1-33
LEARNING CONTROL

Oil pressure control timing is optimally corrected at the time of clutch engagement and disengagement
and controlled to bring the speed-change time to the value preset to the TCM and compensate the
changes of the engine performance and changes of the transmission with time.

When the gear is shifted, the clutch pressure 2 is optimally corrected so that the speed-change time is as
near as the target value
1 preset to the TCM and the changes in the engine performance and the
changes of the transmission with time can be compensated based on the past speed-change results.

When the clutch is operated to shift the gear, the time of the clutch oil pressure release timing 4 on the
disengagement side is optimally corrected so that the changes of the engine rpm
3 is optimum.


Note:

When the battery terminal is disconnected, contents of learning are cleared and resultantly the speed
change shock may increase. After the vehicle has traveled, learning is repeated and the shock
decreases gradually.





Figure 53. Learning Control

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

ON-VEHICLE SERVICE (JR405E) 7A3-1
SECTION 7A3
ON-VEHICLE SERVICE (JR405E)
TABLE OF CONTENTS
PAGE
Description ...................................................................................................................... 7A3 – 2
Automatic Transmission Fluid (ATF) ............................................................................. 7A3 – 2
ATF Level ......................................................................................................................... 7A3 – 2
ATF Change ..................................................................................................................... 7A3 – 3
Transmission Control Module (TCM) ............................................................................ 7A3 – 4
Throttle Position Sensor ................................................................................................ 7A3 – 5
Inhibitor Switch ............................................................................................................... 7A3 – 6
Speed Sensor .................................................................................................................. 7A3 – 8
Turbine Sensor ................................................................................................................ 7A3 – 9
Power and 3rd Start Switch ........................................................................................... 7A3 – 9
Select Lever ..................................................................................................................... 7A3 –10
Shift Cable ....................................................................................................................... 7A3 –13
Solenoids, Oil Pressure Switch and Oil Temperature Sensor .................................... 7A3 –16
Control Valve Assembly ................................................................................................. 7A3 –18
Flushing the Transmission Fluid Cooler and Line ....................................................... 7A3 –19
Transmission Assembly ................................................................................................. 7A3 –20

UNIT REPAIR (JR405E) 7A4-1
SECTION 7A4
UNIT REPAIR (JR405E)
TABLE OF CONTENTS
PAGE
Automatic Transmission Disassembly ..................................................................... 7A4 - 2
Control Valve Assembly ............................................................................................ 7A4 - 11
Control Valve Upper Body ........................................................................................ 7A4 - 18
Control Valve Lower Body ........................................................................................ 7A4 - 23
Oil Pump Assembly ................................................................................................... 7A4 - 28
Clutch Pack (Reverse and High Clutch Assembly) ................................................. 7A4 - 33
Carrier and Low Clutch Assembly ........................................................................... 7A4 - 41
Transmission Case .................................................................................................... 7A4 - 54
Bearing and Bearing Race Installation Position ..................................................... 7A4 - 66
Automatic Transmission Reassembly ..................................................................... 7A4 - 69
Service Standard ....................................................................................................... 7A4 - 83
Special Service Tool .................................................................................................. 7A4 - 85