A132L

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AUTOMATIC TRANSAXLE –

AUTOMATIC TRANSAXLE (A241E, A243L)

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AUTOMATIC TRANSAXLE – Description

DESCRIPTION
General
The A241 E and A243L automatic transaxles are 4–speed transaxles with a lock–up mechanism developed exclusively for the New Celica. The A241 E automatic transaxle is an Electronically Controlled Transaxle (hereafter called ECT). The A243L automatic transaxles arebased on the A240L automatic transaxle. These automatic transaxles have the following features. EThe ”Super– Flow” torque converter is used to improve the transmission efficiency. EWhen shifting the transmission, the engine torque is controlled and the clutch hydraulic pressure in the transmission is electronically controlled to reduce transmission shift shock. (A241 E) E Transaxle control ECU hasbeen integrated with the Engine ECU (A241 E). These automatic transaxles are mainly composed of the torque converter with lock–up clutch, 4–speed planetary gear unit, the hydraulic control system and the electronic control system. To minimize the possibility of incorrect operation of the automatic transaxle, a shift lock mechanism has also been added.

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AUTOMATIC TRANSAXLE – DescriptionGeneral Specifications
Type of Transaxle Type of Engine Stall Torque Ratio Torque Converter Lock–Up Mechanism 1st Gear 2nd Gear Gear Ratio 3rd Gear O/D Gear Reverse Gear Forward Clutch Direct Clutch Number of Discs and Plates (Disc/Plate) Underdrive Clutch 2nd Brake 1st & Reverse Brake Underdrive Brake 2nd Coast Brake (B1) Band Width Type ATF Capacity litter (US qts, Imp. qts) Total Drain &Refill mm (in.)

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AUTOMATIC TRANSAXLE – Operation

OPERATION
Mechanical Operation OPERATING CONDITIONS

Range (i.e., Shift Lever Position)

Gear

No. 1 Solenoid Valve*1

No.2 Solenoid Valve*1 OFF OFF OFF OFF

Park Reverse Neutral

2nd 3rd O/D OFF OFF OFF OFF 2nd 3rd *2 OFF OFF 2nd *2 *1: A241 E Only E: Operating *2: Down–Shift only in the 3rd gear for the 2 range and 2nd gearfor the L range – no up–shift

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AUTOMATIC TRANSAXLE – Operation

FUNCTION OF COMPONENTS
Component Forward Clutch Direct Clutch U/D Clutch 2nd Coast Brake 2nd Brake 1st & Reverse Brake U/D Brake No.1 One–Way Clutch No.2 One–Way Clutch U/D One–Way Clutch Planetary Gears Function Connects input shaft and front planetary ring gear. Connects input shaft and front & rear planetary sun gear.Connects underdrive sun gear and underdrive planetary carrier. Prevents front & rear planetary sun gear from turning either clockwise or counterclockwise. Prevents outer race of F1 from turning either clockwise or counterclockwise thus preventing the front & rear planetary sun gear from turning counterclockwise. Prevents rear planetary carrier from turning either clockwise or counterclockwise.Prevents underdrive sun gear from turning either clockwise or counterclockwise. When B2 is operating, this clutch prevents the front & rear planetary sun gear from turning counterclockwise. Prevents rear planetary carrier from turning counterclockwise. Prevents underdrive planetary sun gear from turning clockwise. These gears change the route through which driving force is transmitted in accordancewith the operation of each clutch and brake in order to increase or reduce the input and output speed.

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AUTOMATIC TRANSAXLE – Operation

FUNCTION OF COMPONENTS (Cont’d)
The conditions of operation for each gear position are shown on the following illustration:

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AUTOMATIC TRANSAXLE – Operation

Hydraulic Control System
The hydraulic control system is composed of the oil pump,the valve body, the solenoid valves, the accumulators, the clutches and brakes, and the governor valve as well as the fluid passages which connect all of these components. Based on the hydraulic pressure created by the oil pump, the hydraulic control system governs the hydraulic pressure acting on the torque converter, clutches and brakes in accordance with the vehicle driving conditions. The...