Operation

OPERATION

1. OPERATING CONDITIONS





2. COMPONENTS FUNCTION











3. 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, 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 clutch, clutches and brakes in accordance with the vehicle driving conditions.
There are 5 solenoid valves on the valve body.
The No. 1 and No.2 solenoid valves are turned on and off by signals from the ECM to control the shift valves, and change the gear shift position.
The No.3 solenoid valve is operated by signals from the ECM to engage or disengage the lockup clutch of the torque converter clutch.
The No.4 solenoid valve is operated by signals from the ECM to control the engagement speed and reduce gear shift shock.
The No.5 solenoid valve is operated by signals from the ECM to regulate the line pressure to throttle pressure.

4. ELECTRONIC CONTROL SYSTEM
The electronic control system for the A340E automatic transmission provides extremely precise control of the gear shift timing and lock-up timing in response to driving conditions as sensed by various sensors located throughout the vehicle and in response to the engine's running condition.
In addition, the ECM control reduces vehicle squat when the shift lever is moved from N to D. The electronic control system is also equipped with a self diagnosis system which diagnoses malfunctions for the vehicle to continue functioning when a malfunction occurs.




The electronic control system can be broadly divided onto three groups, the sensors, ECM and actuators.