System Outline

This system electrically controls the line pressure, Throttle pressure, Lock-Up pressure and accumulator pressure etc. Through the solenoid valve. The electronic controlled transmission is a system which precisely controls gear shift timing and Lock-Up timing in response to the vehicle's driving conditions and the Engine operating conditions detected by various sensors, making smooth driving possible by shift selection for each gear which is the most appropriate to the driving conditions at that time, and controls the Engine torque during shifting to achieve optimum shift feeling.

1. GEAR SHIFT OPERATION
When driving, the Engine warm up condition is input as a signal to TERMINAL B-44 of the Engine Control Module (Engine And Electronic Controlled Transmission ECU) from the Engine coolant temp. sensor (Water Temp. Sensor) and the vehicle speed signal from vehicle speed sensor (Speed Sensor) NO.2 is input to TERMINAL B-23 of the Engine Control Module (Engine And Electronic Controlled Transmission ECU) . At the same time, the Throttle valve opening signal from the Throttle position sensor (Main) is input to TERMINAL B-43 of the Engine Control Module (Engine And Electronic Controlled Transmission ECU) as Throttle angle signal.
Based on these signals, the Engine Control Module (Engine And Electronic Controlled Transmission ECU) selects the best shift position for driving conditions and sends current to the Electronic Controlled Transmission Solenoids.
When shifting to 1st speed, the current flows from TERMINAL B-10 of the Engine Control Module (Engine And Electronic Controlled Transmission ECU) --> TERMINAL 3 of Electronic Controlled Transmission solenoid --> Ground, and continuity to NO.1 solenoid causes the shift (NO.2 solenoid does not have continuity at this time).
For 2nd speed, the current flows simultaneously from TERMINAL B-9 of the Engine Control Module (Engine And Electronic Controlled Transmission ECU) --> TERMINAL 2 of Electronic Controlled Transmission Solenoid --> Ground, and from TERMINAL B-10 of the Engine Control Module (Engine And Electronic Controlled Transmission ECU) --> TERMINAL 1 of Electronic Controlled Transmission Solenoid --> Ground, and continuity to NO.1 and NO.2 solenoids causes the shift. For 3rd speed, there is no continuity to NO.1 solenoid, only to NO.2 solenoid, causing the shift.
Shifting into the 4th speed (Overdrive) occurs when no current flows to NO.1 and NO.2 solenoids. The NO.4 solenoid (For Accumulator Back Pressure Modulation) is installed to adjust the back pressure on the accumulator and control the hydraulic pressure during shifting and Lock-Up in order to provide smooth shifting with little shift shock.

2. LOCK-UP OPERATION
When the Engine Control Module (Engine And Electronic Controlled Transmission ECU) decides, based on each signal, that the Lock-Up condition has been met, the current flows from TERMINAL B-8 of the Engine Control Module (Engine And Electronic Controlled Transmission ECU) --> TERMINAL 3 of the Electronic Controlled Transmission Solenoid --> Ground, causing continuity to the Lock-Up solenoid and causing Lock-Up operation.

3. STOP LIGHT SW CIRCUIT
If the brake pedal is depressed (Stop Light SW ON) when driving in Lock-Up condition, a signal is input to TERMINAL A-4 of the Engine Control Module (Engine And Electronic Controlled Transmission ECU). The Engine Control Module (Engine And Electronic Controlled Transmission ECU) operates and cuts the current to the solenoid to release Lock-Up.

4. OVERDRIVE CIRCUIT
^ O/D Main SW ON
When the O/D Main SW is turned on (SW Point Is Open), a signal is input to TERMINAL A-28 of the Engine Control Module (Engine And Electronic Controlled Transmission ECU) and the Electronic Controlled Transmission Causes shift to overdrive when the conditions for overdrive are met.

^ O/D Main SW OFF
When the O/D Main SW is turned Off (SW Point Is Closed), the current flowing through the O/D Off indicator light flows to Groundby way of the O/D Main SW and causes the O/D OFF indicator light to light up. At the same time, a signal is input to TERMINAL A-28 of the Engine Control Module (Engine And Electronic Controlled Transmission ECU) and the Electronic Controlled Transmission Prevents shift into overdrive.

5. ELECTRONIC CONTROLLED TRANSMISSION PATTERN SELECT SW CIRCUIT
When the Electronic Controlled Transmission Pattern select SW is changed from "Normal" to "Power", the current through the Gaugefuse flows to TERMINAL 4 of Electronic Controlled Transmission Pattern Select SW --> TERMINAL 3 --> TERMINAL B-4 of A/T indicator --> TERMINAL A-23 --> Ground and causes the indicator light to light up. At the same time, the current flows to TERMINAL A-18 of the Engine Control Module (Engine And Electronic Controlled Transmission ECU) and the Engine Control Module (Engine And Electronic Controlled Transmission ECU) performs shift up and shift down at a higher vehicle speed range compared with "Normal" position.

6. KICK DOWN OPERATION
When the Accelerator is depressed further than the full Throttle position while driving, the kick down SW turns ON and its signal is input to TERMINAL A-3 of the Engine Control Module (Engine And Electronic Controlled Transmission ECU). Then, the Engine Control Module (Engine And Electronic Controlled Transmission ECU) controls the current which flows from TERMINAL B-10 and B-9 of the Engine Control Module (Engine And Electronic Controlled Transmission ECU) to the NO.1 and NO.2 solenoids and shifts down by turning the solenoids ON and OFF.

7. CRUISE CONTROL
When cruise control operation is selected a signal is input to TERMINAL A-12 of the Engine Control Module (Engine And Electronic Controlled Transmission ECU) from cruise control ECU. As a result, the Engine Control Module (Engine And Electronic Controlled Transmission ECU) operates and controls overdrive, Lock-Up and so on for smooth driving.