Overdrive Assembly: Description and Operation

Overdrive Cut System (A240L)
In addition to a function which cuts the overdrive when the water temperature is low, the A240L automatic transaxle also has a new function which cuts the overdrive when the throttle valve opening angle reaches 70% or more during overdrive operation.

The overdrive cut system is controlled by the Engine ECU.




CONSTRUCTION
The overdrive cut system can be broadly divided into three sections, the sensors, the ECU and the actuator.

OPERATION
1. O/D Main Switch in ON Position
When the water temperature is 55 °C (131 °F) or below, the O/D solenoid is turned ON and the overdrive is cut.

If the water temperature is 55 °C (131 °F) or more and the following conditions are both fulfilled, the O/D solenoid is turned ON and the overdrive is cut:
- Vehicle speed less than or equal to 125 km/h (78 mph)
- Throttle valve opening angle is 70% or more.

2. O/D Main Switch in OFF Position
The O/D solenoid remains ON and the overdrive is cut.