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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
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03-133660-01
2) Transaxle Cooling
The transaxle cooling system ensures rapid warm-up and constant operating temperature resulting in
reduced fuel consumption and refined shift quality.
It also includes a cooler by-pass within the hydraulic system to allow sufficient lubrication to the transaxle
drivetrain in the event of a blockage in the transaxle cooler.
3) Shift Strategy
Gear Change ▶
Transaxle gear change is controlled by the
TCU. The TCU receives inputs from various
engine and vehicle sensors to select shift
schedules and to control the shift feel and
torque converter clutch (TCC) operation at each
gear change.
Coast down ▶
Coast down down shifts occur at 0% pedal
when the vehicle is coasting down to a stop.
Torque Demand ▶
Torque demand down shifts occur
(automatically) when the driver demand for
torque is greater than the engine can provide at
that gear ratio. If applied, the transaxle will
disengage the TCC to provide added
acceleration.
Page 876 of 1082

03-16
4. LIMP HOME MODE
When the transaxle is defective ▶
In the event of a system fault, the TCU also provides for failure mode effect control (FMEC) to maintain
maximum functional operation of the transaxle. (There are 3 FMEC modes, mechanical limp-home
mode, electrical limp-home mode, limp-home mode C.)
In the event of a total loss of control or electrical power, the basic transaxle functions (Park, Reverse,
Neutral and Drive) are retained. The 4th and reverse gear ratios with the torque converter clutch in the
unlocked state are the retained gear states the hydraulic system supports without any electrical
assistance. (Mechanical limp-home)
If the speed sensor circuit is failed, the gear is fixed to 4th gear, but manual shifting
<004f00590095008b02e9005a0099008b02e9005b009b008f005000470090009a00470088009d008800900093008800890093008c0055004f006c0093008c008a009b00990090008a00880093004700930090009400970047008f00960094008c0047009400
96008b008c0050>
If the inhibitor switch signals are invalid, shifting to1st and 2nd gear is forbidden. (Limp-home C)
The TCU communicates with other vehicle electronic control modules by the controller area network
(CAN). If a major fault is developed, the transaxle may not accomplish the intelligent shift control. The
TCU controls the transaxle with preset values.
The TCU also provides for transaxle diagnostics, which meet the requirements of OBD II regulation,
monitoring all components which may effect vehicle emissions. 1.
2.
3.
4.
5.
6.
Towing the automatic transaxle equipped vehicle ▶
Flat-bed equipment is the best method of moving a disabled vehicle to avoid any damages.
For AWD vehicle: The vehicle must be towed with a wheel lift and dollies or flatbed equipment with
all the wheels off the ground.
For 2WD vehicles: It is acceptable to tow the vehicle with the rear wheels on the ground without
dollies and the front wheels off the ground. When being towed by a commercial towtruck and
wheel dollies are not available, the front of the vehicle should be lifted, not the rear. -
-
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03-20
2) Operation in Each Gear Position
(1) Neutral/Park
Lower & reverse brake (LR/B) op<008c00990088009b008c008b004702e700470076009d008c0099008b00990090009d008c0047004f00760056006b00500047008f009c0089004700930096008a0092008c008b004702e7004700740090008b008b0093008c0047004d00470099008c008800
9900470047004f00740070006b0047004d0047>
REAR) P/C locked
<007000950097009c009b0047009a008f0088008d009b004700990096009b0088009b008c008b004702e700470079008c008800990047009a009c00950047008e008c00880099004700990096009b0088009b008c008b004702e700470079008c0088009900
47009000950095008c00990047009700900095009000960095> reverse rotated → Rear outer
<009700900095009000960095004700990096009b0088009b008c008b004702e700470079008c008800990047008800950095009c0093009c009a0047008e008c00880099004700990096009b0088009b008c008b004702e70047006d009900960095009b00
47008800950095009c0093009c009a0047008e008c00880099> rotated → Front pinion
<00990096009b0088009b008c008b004702e70047006d009900960095009b0047009a009c00950047008e008c0088009900470099008c009d008c0099009a008c004700990096009b0088009b008c008b004702e70047007c0095008b008c0099008b009900
90009d008c0047004f007c0056006b00500047008f009c0089> reverse rotated
Input shaft rotated → Overdrive clutch (OD/C) retainer rotated
Input shaft rotated → 35R clutch rotated -
-
-
-
Power flow ▶
Description 35R C OD C 26 B UD B LR B O.W.C
P.N●
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(2) Reverse (3.385)
Middle planetary gear locked, middle sun gear rotated
When the sun gear rotates with the planetary gear locked in middle planetary gear set, the annulus
gear (front planetary gear) rotates in reverse direction with decreased speed and the power flows
through the front planetary gear.
The rear planetary gear set reduces the rotating speed of rear & front annulus gears and the front
planetary gear set rotates the front sun gear in reverse direction without load. -
-
-
Power flow ▶
Description 35R C OD C 26 B UD B LR B O.W.C
R●●
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03-22
(3) 1st Drive Gear (4.212)
Front sun gear and middle & rear planetary gears locked, and rear sun gear always rotated
When the rear sun gear rotates, the rear planetary gear set reduces the speed at first, and then the
reduced power is transferred to rear & front annulus gear. The power is secondarily reduced at front
planetary gear locked with sun gear and flows to front planetary gear.
At this moment, the middle sun gear rotates in reverse direction without load (idling) by the rotation of
middle annulus gear integrated with front planetary gear. -
-
-
Power flow ▶
Description 35R C OD C 26 B UD B LR B O.W.C
1ST●○●
Operated below 5 km/h of vehicle speed O :
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03-233660-01
(4) 2nd Drive Gear (2.637)
Front sun gear and middle sun gear locked, rear sun gear always rotated
When the sun gear rotates, the power is transferred to the rear & front annulus gears, and then the
reaction power from the front planetary gear and middle annulus gear locked with sun gear is
transferred to middle & rear planetary gear to circulate the power. Accordingly, the power flows
through the front planetary gear while keeping the balance. -
-
Power flow ▶
Description 35R C OD C 26 B UD B LR B O.W.C
2nd●●
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03-24
(5) 3rd Drive Gear (1.800)
Front sun gear locked, middle & rear sun gear rotated
When the middle sun gear and rear sun gear rotate, the power is transferred to the rear & front
annulus gears, and then the reaction power from the front planetary gear and middle annulus gear
locked with sun gear is transferred to middle & rear planetary gear to circulate the power.
Accordingly, the power flows through the front planetary gear while keeping the balance. -
-
Power flow ▶
Description 35R C OD C 26 B UD B LR B O.W.C
3rd
●●