Page 848 of 1082

02-14
5. TRANSAXLE ELECTRONIC CONTROL SYSTEM
1) General Information
The transmission control unit (TCU) and its input/output network control the following transmission
operations:
Shift timing
Line pressure
Clutch pressure (shift feel)
Torque converter clutch -
-
-
-
also uses these signals when determining transaxle operating strategy. Using all of these input signals,
the TCU can determine when the time and conditions are right for a shift, or when to apply or release the
torque converter clutch. It will also determine the pressure needed to optimise shift feel. To accomplish
this, the TCU operates six variable bleed control solenoids and four on/off solenoids to control transaxle
operation.
2) TCU (Transmission Control Unit)
The transaxle control unit (TCU) is mounted
under the driver's seat and controls the operation
of the transaxle.
The TCU is activated and deactivated by the
ignition power supply and is connected to the
transaxle link harness by a 26 pin connector. The
TCU processes information received from internal
sensors and signals received across the CAN
bus in analogue and digital forms such as:
Transaxle input speed
Transaxle output speed
Accelerator pedal position
Gear selector position
Engine torque
Engine speed
Transaxle fluid temperature
Brake pedal status
Engine oil temperature
Engine coolant temperature
Ambient air temperature
Barometric pressure -
-
-
-
-
-
-
-
-
-
-
-
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02-153680-01
This information is used by the TCU to decide which shift pattern to select and for shift energy
management. Electro-hydraulic solenoid valves and variable bleed solenoids control the transaxle gear
changes.
Six variable bleed solenoids and four on/off solenoids are used to direct transaxle fluid flow to control the
fluid pressure within the three clutches and two bands. Separate pressure regulators are used
exclusively for torque converter clutch control and main transaxle line pressure.
The TCU monitors all TCU inputs and outputs to confirm correct system operation. If a fault occurs the
TCU is able to perform default action and inform the driver of the problem through the instrument cluster
warning lights. Detailed information is available via trouble codes which can be read with the service tool.
Page 850 of 1082

02-16
3) Shift Map Selection
The driver can manually select between normal (S) and winter modes (W) via the mode switch.
Depending on the transaxle temperature, uphill and downhill grades and altitude, shift maps will be
selected by the TCU to suit the driving conditions. The following maps are available.
Standard (Normal) Mode ▶
Normal Mode is selected when the lever is in the D position with the mode switch in the normal (S)
position and the transaxle is within normal temperature ranges. Shift schedule points are optimised for
fuel efficiency and general driving conditions.
Uphill and Downhill Mode ▶
In this mode, depending on the load of the vehicle, adaptive shift maps are selected to progressively
adjust the shift points and torque converter lock points.
Altitude Mode ▶
Shift points are automatically adjusted at higher altitudes to compensate for changes in engine torque
where the torque produced by the engine is greatly reduced by the effects of reduced barometric
pressure and temperature.
Winter (W) Mode ▶
When winter mode is selected, starting in second gear is facilitated and the WINTER mode indicator
light is switched ON. To prevent wheel spin on slippery surfaces, the transmission will not allow first gear
unless manually overridden.
Warm up Schedule ▶
<007c009a008c008b0047009b00a000970090008a00880093009300a00047009e008f008c00950047009b009900880095009a0088009f0093008c0047008d0093009c0090008b0047009b008c00940097008c00990088009b009c0099008c00470090009a00
470089008c00930096009e00470059005700b6006a0055>
The torque converter will not lock-up below 20°C to assist in transaxle warm-up.
Hot Mode ▶
<007b008f008c0047008f0096009b004700940096008b008c00470090009a0047009700990096008e0099008c009a009a0090009d008c009300a0004700880097009700930090008c008b00470089008c009b009e008c008c00950047009b008c0094009700
8c00990088009b009c0099008c009a00470096008d00470058>10° ~ 200°C. The torque
converter lock-up is increased to prevent heat generation by the torque converter.
Activation of the hot mode inhibits other transmission performance features including uphill and downhill
compensation and altitude compensation. Some degradation in shift feel may be experienced as the
torque converter is not unlocked during shifting.
Cruise Control Mode ▶
When cruise control is activated the engine ECU may request the transaxle to downshift under trailing
throttle conditions to increase engine braking.
Above 110℃the electrical radiator fans are switch ON
Above 130℃the engine torque will be reduced and the W light on the instrument cluster will flash
Above 200℃the transaxle will neutralise until the fluid tem
perature falls below 200°C as a final
protection.
Page 851 of 1082
02-173680-01
6. CAN NETWORK
The TCU sends signals to be used by other vehicle systems via the CAN bus, such as:
Selector lever position
Selected gear state
Manual mode activation
Output torque
Transaxle fluid temperature
Engine torque reduction requests -
-
-
-
-
-
Schematic Diagram of Network Communication ▶
Page 853 of 1082
02-193680-01
2) Power Flowing Sequence
Torque converter Input shaft Front planetary gear
C2 clutch Forwarding sun gear Rear planetary gear
C1 clutch Center support Intermediate shaft
assembly
inal reduction and
differential gearThis is a fluid clutch.
Transfers the power from
engine to transaxle and
amplifies the torque.Transfers the power
from torque converter
to front planetary
gear.Generates the gear
ratio and transfers the
power.
Engaged by hydraulic
pressure and transfers the
power to C1 clutch.Transfers the power from
torque converter to rear
planetary gear.Generates the gear ratio
and transfers the power.
Engaged by hydraulic
pressure and transfers the
power to C1 clutch.Transfers the power from
input shaft to intermediate
shaft.Changes the rotating direction
and generates the final
reduction rear ratio.
Generates the final reduction gear ratio and performs
the differential function.
Transfers the power to constant velocity shaft.
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03-4
2. GENERAL INFORMATION
Automatic transaxle (6F24) ▶
The Model 6F24 six speed automatic transaxle is
available in two variants: four wheel drive and two
wheel drive.
Six forward speeds
One reverse gear
A toruqe converter with an integral converter lock-
up clutch with slip control capabilities
Planetary gear-set (3EA)
Clutches (2EA)
Brake (3EA)
O.W.C (1EA)
All hydraulic functions are directed by electronic
solenoids to control: -
-
-
-
-
-
-
-
Engagement feel
Shift feel
Shift scheduling
Modulated torque converter clutch
applications 1)
2)
3)
4) Inhibitor switch
Oil pan
Torque converter
TCU (located under driver's seat) ▶
TCU is located under the driver's seat and controls
the transaxle operations.
TCU receives and uses the signals from sensors
and switches through CAN bus with analog and
digital types. Driver seat
TCU
Passenger
seat
Page 866 of 1082
03-6
3. SPECIFICATIONS
1) Specifications
Type/Weight 6F24 6-speed automatic transaxle /
approx. 86 kg (including ATF)
TORQUE 230 Nm
Overall length / Center length 373.1 mm / 204 mm
Descriptions Specification
Gear ratio 1st gear 4.212
2nd gear 2.637
3rd gear 1.800
4th gear 1.386
5th gear 1.000
6th gear 0.772
Reverse gear 3.385
Shift pattern Variable
Shift range 4 Range (P-R-N-D) + Manual mode
Shift range valve VFS : 6EA
Planetary gear 3EA (Front, Middle, Rear)
Clutch 2EA
Brake 3EA
O.W.C 1EA
Oil Type ATF SP-IV or SP-IV M
Capacity approx. 7.1 L
Change interval Maintenance free. However, under the severe
conditions or commercially used, change the oil at
every 100,000 km (EU: 90,000 km).
Resistance of oil
temperature sensor-20Approx 15.6kΩ
0Approx 5.88kΩ
20Approx 2.51kΩ
100Approx 0.18kΩ
Weight 2WD 87.5kg
4WD 88.5kg
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03-73660-01
4. COMPONENTS
HPT 6A/T (6F24)
One-way clutchTorque converter
(with slip lockup)
Oil pumpHarness
Valve bodySide gearDriven gear