Tcm ISUZU TF SERIES 2004 Workshop Manual
Page 3979 of 4264
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
Page 3980 of 4264
7A1-34 CONSTRUCTION AND FUNCTION
MAJOR INPUT/OUTPUT COMPONENT AND THEIR FUNCTIONS
Speed sensor Detects output shaft revolution and sends rpm signal to TCM.
Turbine sensor Detects input shaft revolution and sends rpm signal to TCM.
Engine speed sensor Inputs engine revolution from engine control computer.
Brake switch Detects brake pedal operated by the driver and sends signal to
TCM.
Inhibitor switch Detects select lever position and sends signal to TCM.
Mode select switch Detects "Power Drive" or "3rd Start" selected by the driver and
sends signal to TCM.
4L switch (4WD Only) Inputs 4L mode from transfer control computer.
ATF thermo sensor Detects ATF temperature and sends signal to TCM.
High clutch oil pressure switch Detects high clutch supply oil pressure and sends signal to
TCM.
2-4 brake oil pressure switch Detects 2-4 brake supply oil pressure and sends signal to
TCM.
Low & Reverse brake oil pressure switch Detects low & reverse brake supply oil pressure and signal to
TCM.
Throttle position sensor Inputs throttle opening angle from engine control computer.
Input
TCM Judges necessary line pressure, gear shifting point and lock-up
operation based on electrical signals from switches and
sensors and sends appropriate signals to solenoids.
Line pressure solenoid Regulates oil pump delivery pressure to the appropriate line
pressure for current driving condition based on signal from
TCM.
Low clutch solenoid Selects appropriate gear shifting position for current driving
condition and regulates low clutch supply oil pressure based on
signal from TCM.
High clutch solenoid Selects appropriate gear shifting position for current driving
condition and regulates high clutch supply oil pressure based
on signal from TCM.
2-4 brake solenoid Selects appropriate gear shifting position for current driving
condition and regulates 2-4 brake supply oil pressure based on
signal from TCM.
Low & Reverse brake solenoid Selects appropriate gear shifting position for current driving
condition and regulates low & reverse brake supply oil
pressure based on signal from TCM.
Lock-up solenoid Regulates lock-up pressure to appropriate level for current
driving conditions based on signal from TCM.
Mode indicator lamp Indicates POWER DRIVE or 3rd START switch position.
Speed meter signal (2WD Only) Outputs vehicle speed to speed meter.
A/T OIL TEMP indicator lamp Indicates A/T OIL TEMP indicator lamp in case of high
temperature.
Output
CHECK TRANS indicator lamp Indicates CHECK TRANS indicator lamp in case of
malfunction.
Page 3981 of 4264
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
Page 3997 of 4264
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
Page 3998 of 4264
7A2-6 DIAGNOSIS (JR405E)
BASIC TROUBLE SHOOTING
Transmission fluid pressure together with clutch and brake friction and other important transmission functions are
controlled by electrical signal from the Transmission Control Module (TCM).
Random diagnosis can produce inaccurate and misleading indications. It is important that diagnosing procedure be
carried out systematically.
Carefully follow the sequence outlined below to diagnose automatic transmission assembly.
Verify Customer Complain
Preliminary Check
(Visual Check/Test Drive)
Compare to Same Model
(If Available)
Check Service Bulletin
DTC Check
(Self-diagnosis/Tech 2)
Go to Symptom Diagnosis
Stall Test
Line Pressure Test
Transmission Overhaul
Repair & Verify Fix
Transmission Overhaul
Transmission Overhaul
Go to DTC Chart
Go to Intermittent Diagnosis NG
Follow the instructions
NG
No Instruction
NG
OK
NO DTC
Not Solved
OK
OK
Follow the Bulletin
(Once Clear Memory) Restored
Not Stored
Use Service Programming
System (SPS)
Not Solved
Page 3999 of 4264
DIAGNOSIS (JR405E) 7A2-7
CHECK TRANS INDICATOR & SELF DIAGNOSIS
CHECK
TRANS
Warning to the driver
"CHECK TRANS" is ON during 3 seconds at key switch ON
position.
When trouble has occurred to electrical components,
"CHECK TRANS" lamp is blinked (1.25 Hz) even during
driving to warn the driver.
The trouble is recorded by trouble code in TCM. When
temporary trouble code has been canceled, the "CHEC
K
TRANS" lamp stops blinking. This blinking can be stopped
by setting the key off. But the trouble code remains
memorized in TCM.
Key SW ON
ON
OFF
3 Sec.
(Lamp Check)
Illumination Pattern at Normal Condition
NOTE:
1. If the "CHECK TRANS" lamp is staying ON always at key
switch ON position, this means that connection between the
lamp and TCM is shorted to ground.
Verify connection and wire between the TCM A20 terminal
and lamp short to ground.
2. If the "CHECK TRANS" lamp is staying OFF at key switch
ON position (Engine off), this means that connection
between the lamp and TCM is opened or meter fuse (15A)
is burnt out.
Verify connection and wire between the TCM A20 terminal
and lamp open circuit and meter fuse (15A).
Key SW ON 0.4 Sec.
ON
OFF
3 Sec.
3.2 Sec.
0.4 Sec.
(Lamp Check)
Illumination Pattern at Trouble Condition
Off Acc On V Acc
CHECK TRANS
Meter
Meter Fuse C5 (15A)
Fuse Box & Relay Box
(Cabin)
TCM
Page 4004 of 4264
7A2-12 DIAGNOSIS (JR405E)
F0: Diagnostic Trouble Code
F0: Read DTC Infor As Stored By ECU
F1: Clear DTC Information
F1: Data Display
F2: Snapshot
F3: Miscellaneous Test
F0: Lamp
F0: Power Lamp Test
F1: 3rd Start Lamp Test
F2: AT Oil Temperature Lamp Test
F3: Transmission Check Light Test
F1: Solenoids
F0: Low & Reverse Brake Solenoid
F1: 2-4 Brake Solenoid
F2: High Clutch Solenoid
F3: Low Clutch Solenoid
F4: Line Pressure Solenoid
F5: Lock Up Duty Solenoid
F4: Programming
F0: Program VIN
F1: Lock ECU
F0: Diagnostic Trouble Code
The purpose of the "Diagnostic Trouble Codes" mode is to
display stored trouble code in the TCM.
When "Clear DTC Information" is selected, a "Clear DTC
Information", warning screen appears. This screen informs you
that by cleaning DTC's "all stored DTC information in the TCM
will be erased".
After clearing codes, confirm system operation by test driving
the vehicle.
F1: Data Display
The purpose of the "Data Display" mode is to continuously
monitor data parameters.
The current actual values of all important sensors and signals
in the system are display through F1mode.
See the "Typical Scan Data" section.
F2: Snapshot
"Snapshot" allows you to focus on making the condition occur,
rather than trying to view all of the data in anticipation of the
fault. The snapshot will collect parameter information around a
trigger point that you select.
F3: Miscellaneous Test:
The purpose of "Miscellaneous Test" mode is to check for
correct operation of electronic system actuators.
F4: Programming (Factory Use Only):
The purpose of "Programming" is to program VIN in the ECM
and lock the programmed data.
Page 4008 of 4264
7A2-16 DIAGNOSIS (JR405E)
INTERMITTENT DIAGNOSIS
If the Tech 2 displays any codes as intermittent, or if after a test drive any codes does not reappear, the problem is
most likely a faulty electrical connection or loose wiring.
Terminals should always be the prime suspect.
Intermittent rarely occur in sophisticated electronic components such as the TCM.
When an intermittent problem is encountered, check suspect circuits for:
Poor terminal to wire connection.
Terminals not fully seated in the connector body.
Improperly formed or damaged terminals.
Loose, dirty or damaged terminals.
Any time you have an intermittent in more than one circuit, check whether the circuits share a common ground
connection.
Pinched or damaged wires.
Electric interference.
Check for improperly installed electrical options, such as light, radios, etc.
Use the F2: Snapshot mode of the Tech 2 to help isolate the cause of an intermittent fault. The snapshot mode will
record information before and after the problem occurs. Set the snapshot to "Trigger" on the suspected code or, if
you notice the reported symptom during test drive, trigger the snapshot manually.
After the snapshot has been triggered, command the Tech 2 to play back the flow of data recorded from each of the
various sensors. Sings of intermittent fault in a sensor circuit are a sudden unexplainable jump in data values out of
the normal range.
Page 4014 of 4264
7A2-22 DIAGNOSIS (JR405E)
6. If you select “continue”, you have to select “Model Year”, “Vehicle Type”.
7. After that, push button and turn Ignition switch tuned on, off, on following Tech-2 display. Tech-2 will read
information from controller after this procedure.
8. During obtaining information, Tech-2 is receiving information from the control unit ECM and TCM at the same
time. With VIN not being programmed into the new control unit at the time of shipment, "obtaining
information" is not complete (because the vehicle model, engine model and model year are specified from
VIN). For the procedure get additional information on vehicles, instruction will be provided in dialog form,
when TIS2000 is in operation.
9. Following instructions by Tech-2, push the "Exit" switch of Tech-2, turn off the ignition of the vehicle and turn
off the power of Tech-2, thereby removing from the vehicle.
3. Data Exchange
1. Connect Tech-2 to P/C, turn on the power and click the "Next" button of P/C.
2. Check VIN of the vehicle and choose "Next".
3. Select “Transmission” in the “System Type” selection.
4. When a lack of data is asked from among the following menu, enter accordingly.
Select following Menu
Model Year
Model
Engine type
Destination code (vehicles for general export)*1
* 1: How to read the destination code:
Destination code can be read from service ID Plate affixed on vehicle, while on service ID Plate the destination
code is described at the right-hand edge of Body Type line. In the figure, the destination code can be read as "RR3"
for Australia.
Page 4015 of 4264
DIAGNOSIS (JR405E) 7A2-23
4. After choosing the data, click the "Next" button.
5. 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.
6. "Data Transfer" comes on display. The progress of downloading will be displayed on the screen in the form of
bar graph.
7. Upon finishing the data transfer, turn off the power of Tech-2, removing from P/C.
4. Programming of TCM
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 "F1: Programming 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.