Page 3977 of 6020
TRANSMISSION CONTROL SYSTEM (AW30–40LE) 7A2-11
Control System Diagram
RTW 77AXF000301
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7A2-12 TRANSMISSION CONTROL SYSTEM (AW30–40LE)
Control and Functions
Item Description
Shift and lock-up control Shift and lock-up points can be controlled in accordance with output of S1, S2, and SL solenoids based on "Shift-map" made up of vehicle speed and the opening.
Overdrive off cut control W hen the select lever is operated from D to 3, if the vehicle speed is more than 142km/h (89mph), TCM enables to remain overdrive in order to prevent over rev.
Lock-up cut control Lock-up is inhibited with following condition in order to improve the shift feeling.
• 1st gear
• Idling
• Operating brake switch
• L position
• During shift change
Driveng mode select control
• The TCM selects a suitable driving mode from the ten kinds for the variety
driving condition.
1) Normal mode
2) Power mode
3) 3rd start mode
4) HOT mode
5) L4 mode
6) Up slope1 mode
7) Up slope2 mode
8) Down slope mode
9) Auto cruise mode
10) W arm up mode • The priority of driving mode
Normal < Power < Up slope1 < Up slope2 < Down slope < L4 < W arm up < Auto
cruise < 3rd start < HOT
Oil temperature compensation
control If the ATF temperature exceeds 130
°C (266 °F), the TCM selects the HOT mode
shift pattern for lock-up, thus preventing the oil temperature from rising. (The HOT
mode is released, if the ATF temperature is less than 115 °C /239 °F.)
3rd start mode control By selecting 3rd start mode, the vehicle starting can be controls smoothly on low
frictional road like a snowy or muddy.
1. Enable condition a) The gear select position is "D" only.
b) Vehicle speed is less than 11km/h (7mph).
c) Transmission oil temperature is less than 120 °C (248 °F).
d) Accelerator opening is less than 8%.
e) Except 3rd start mode.
2. Disable condition a) Turning off the 3rd start mode switch
b) Shifting select position to "3", "2", or "L"(3rd start mode is not canceled b
y
selecting "N", "R", or "P")
c) Ignition key is turned off.
d) Vehicle speed is more than 35km/h (22mph).
L4 mode control The TCM detects whether the transfer is engaged in high or low based on L4 switch
signal, and selects the "Shift-map".
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TRANSMISSION CONTROL SYSTEM (AW30–40LE) 7A2-13
Item Description
Reverse lock out control If the select lever is moved to "R" position during forward driving, the TCM prohibits
reverse driving by turn off the S1 and turn on the S2 for prevention of danger and
protection of the automatic transmission.
1. Enable condition a) Vehicle speed is more than 11km/h (7mph).
2. Disable condition a) Vehicle speed is less than 9km/h (6mph).
b) W hen except "R" position is detected.
Auto cruise mode control If the auto cruise control can’t keep the setting speed like a uphill driving, the TCM selects the auto cruise mode shift pattern for downshifting, thus keeping the vehicle
speed.
W arm-up mode control TCM selects the warm-up mode shift pattern in engine cold condition for improvement of drivability and facilitation of warm-up.
Squat control W hen the TCM detects N→D garage shift, the TCM controls 1-3-1 shift by setting
timer, in order to improve the shift feel at N →D.
Coast down control The TCM switches to the coast down control at the coasting, in order to reduce the
roughness of shifting.
Uphill control W hen the TCM detected uphill, the TCM automatically switches to the uphill mode
in two-stage in proportion to inclination pitch to prevent the busy shifting and to
obtain an enough torque.
Downhill control W hen the TCM detected downhill, the TCM automatically switches to the downhill
mode, and shifts to the 3rd or keeps in the 3rd in order to prevent the vehicle
acceleration. Then, the brake load is reduced by a moderate engine brake and fuel
consumption is improved by the fuel cut.
Line pressure control The TCM controls the impressed current of the pressure control solenoid based on the throttle opening, and regulates suitable throttle pressure.
Engine truque management
control The TCM controls engine torque for improvement of shift quality or durability under
the following conditions.
• Upshift and downshift
• Garageshift
Indicate driving mode function The TCM indicates the following driving mode on instrument panel.
• Power mode
• 3rd start mode
Indicate oil temperature
warning function If the transmission oil temperature sensor senses that transmission oil temperature
is greater than 146 °C (295 °F) , the TCM turns on ATF warning lamp. (The warning
lamp is turned off, if oil temperature is less than 126 °C/ 259 °F .)
Fail-safe function W hen trouble occurs to vehicle sensor and each solenoid, TCM automatically exerts
fail-safe control not to spoil driveability.
• This control is exerted when sensor or actuator is in trouble, while TCM works
normally.
• The "CHECK TRANS" light flashes to alert the driver, and the transmission
must be manually shifted as follows.
Select lever position Gear position
D 4 (Fourth)
3 4 (Fourth)
2 3 (Third)
L 3 (Third)
R Reverse
Shift are firmer to prevent clutch slip and consequent wear. The fault should be
corrected as soon as possible.
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7A2-14 TRANSMISSION CONTROL SYSTEM (AW30–40LE)
Item Description
Diagnosis function
• If there is an abnormality in vehicle sensors, each solenoid (S1, S2, SL, STH),
or throttle position sensor, "CHECK TRANS" lamp is actuated to warn the drive.
But when the abnormality items have been restored to normal, the light does
not blink.
• Faulty parts are memorized in TCM. If self-diagnosis start signal is inputted,
"CHECK TRANS" lamp is blinked and results of diagnosis are indicated. A
history of faults remains recorded even when IGN switch is off. If DG1 switch
signal is inputted, or by using F1: Clear DTC Information for TECH 2, the
records can be erased.
TECH 2
• Output of control data in the TCM
• Actuator (Solenoid) operation check
• Erasure of trouble code
• Output of DTC code
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TRANSMISSION CONTROL SYSTEM (AW30–40LE) 7A2-15
Functions of Input / Output Components
RTW 77AXF000701
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7A2-16 TRANSMISSION CONTROL SYSTEM (AW30–40LE)
CAN bus systems in automatic
transmission control (AW30-40LE)
The automatic transmission control system in AW 30-
40LE uses high speed CAN bus system .The individual
CAN bus systems are connected via two interfaces and
can exchange information and data. This allows control
modules that are connected to different CAN bus
systems to communicate.
High speed CAN bus
Transmission control module in the vehicle that require
continuous, rapid communication are connected to the
high speed CAN bus. For example, the automatic
transmission is continuously notified of the current
engine load status. Since the automatic transmission
control module has to react immediately to load status
changes, rapid communication is required between the
engine control module and the automatic transmission
control module. The high speed CAN bus in the AW 30-
40LE is designed as a two-wire CAN bus (twisted pair).
The wires are shielded and twisted. The transfer rate is
500 K baud.
RUW 37ASF000401
Diagnosis
Electronic Diagnosis
How To Diagnose The Problem
1. To avoid incorrect diagnostics, this book needs to
be followed accurately. Unless stated, do not jump
directly to a section that could contain the
solution. Some important information may be
missed.
2. The sections in CAPITALS and bold are the main
sections that can be found in the contents.
3. The go to “SECTION” means to continue to check
going to the “section”.
4. The go through “SECTION” means to go through
the “section” and then to go back to the place the go
through was written.
5. BASIC ELECTRIC CIRCUITS:
You should understand the basic theory o
f
electricity. This includes the meaning of voltage,
amps, ohms, and what happens in a circuit with an
open or shorted wire. You should also be able to
read and understand wiring diagrams.
Check Trans Indicator
Find CHECK TRANS indicator and verify if it is
A. Flashing: Go to On-Board Diagnostic (OBD)
System Check.
B. Staying on: Go through “Check Trans” Check.
C. Is never “ON” when the ignition key is turned on: Go through “Check Trans” Check
D. Is “ON” during 3 seconds at ignition but “OFF” after: Normal operation. No DTC or malfunction.
RTW 77ASH000101
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TRANSMISSION CONTROL SYSTEM (AW30–40LE) 7A2-17
Normal
C07RY005-1
Abnormal
C07RY00042-1
On-Board Diagnostic (OBD) System Check
This test determines if the transmission or its input or
output connections or sensors are failing.
1. Connect the Tech 2: Go through Tech 2 Operating.
2. Turn on the ignition but not the engine.
3. Push “F0” on Tech 2 to see the Diagnostic Trouble Code (DTC):
4. Do you have a DTC? YES: write down all code numbers and do the DTC
CHECK
NO: the DTC can not help you find the problem.
1. Go through “Check Trans” Check
2. If it is flashing and the flash is 0.4 seconds “ON”
and 0.4 seconds “OFF”, this means that you
should have a DTC stored. Please recheck go
to On-Board Diagnostic (OBD) System Chec
k
and if you find the same problem, replace the
Transmission Control Module (TCM).
“Check Trans” Check
1. Indicator is “ON” during 3 seconds at ignition but it
is “OFF” after the engine starts. The indicator is
working normally go to On-Board Diagnostic
(OBD) System Check .
RTW 77ASH000101
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7A2-18 TRANSMISSION CONTROL SYSTEM (AW30–40LE)
Normal
C07RY005-1
2. Indicator is flashing and the flash is 0.4 seconds
“ON” and 0.4 seconds “OFF” always when ignition is
on (engine cranked or not). This means that there is
a malfunction. Go to On-Board Diagnostic (OBD)
System Check .
Abnormal
C07RY00042-1
3. Indicator is staying “ON” always when Ignition is
“ON”.
1. This means that connection between the lamp
and the indicator control unit is shorted to
ground.
2. Verify if instrument panel terminal 25 o
f
connector B–23 is shorted to ground.
3. Verify if the indicator control unit connector C–
95 terminal 3 is shorted to ground.
4. Verify that the instrument panel terminal 8 o
f
connector B–24 is connected to battery.
5. If a problem was solved: Go to Check Trans
Indicator .
NO: Replace Transmission Control Module
(TCM).
4. Indicator is staying “OFF” with the ignition “ON”
(engine “OFF”).
1. This means that connection between the lamp
and the indicator control unit is shorted to
battery or opened.
2. Verify if instrument panel terminal 25 o
f
connector B–23 is shorted to battery or open.
3. Verify if the indicator control unit connector C–
95 terminal 3 is shorted to battery or open.
4. Verify that the instrument panel terminal 25 o
f
connector B–23 is connected to battery. If not,
check the meter fuse and the connections
(terminal 2 of connector H–7) voltage.
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