Honda Accord 2008 Manual page 915

07/11/02 08:47:17 61TA0000_140_0072
Automatic Transmission
System Description (cont'd)
Lock-up System
The lock-up mechanism of the torque converter clutch operates in D (2nd, 3rd, 4th, and 5th gears), and in D3 (2nd and
3rd gears). The pressurized fluid is drained from the back of the torque converter through a fluid passage, causing the
torque converter clutch piston to be held against the torque converter cover. As this takes place, the mainshaft rotates
at the same speed as the engine. Together with the hydraulic control, the PCM optimizes the timing and volume of the
lock-up mechanism. When shift solenoid valve E is turned on by the PCM, shift solenoid valve E pressure switches the
lock-up shift valve on and off. A/T clutch pressure control solenoid valve A and the lock-up control valve control the
amount of the lock-up.
Torque Converter Clutch Lock-up ON (Engaging Torque Converter Clutch)
Fluid in the chamber between the torque converter cover and the torque converter clutch piston is drained off, and
fluid entering from the chamber between the pump and the stator exerts pressure through the torque converter clutch
piston against the torque converter cover. The torque converter clutch piston engages with the torque converter cover;
the torque converter clutch lock-up is ON, and the mainshaft rotates at the same speed as the engine.
＊０１
Power flow
The power flows by way of:
Engine
↓
Drive plate
↓
Torque converter cover
↓
Torque converter clutch piston
↓
Damper spring
↓
Turbine
↓
Mainshaft
Torque Converter Clutch Lock-up OFF (Disengaging Torque Converter Clutch)
Fluid enters into the chamber between the torque converter cover and the torque converter clutch piston and passes
through the torque converter and goes out through the chambers between the turbine and the stator, and between the
pump and the stator. As a result, the torque converter clutch piston moves away from the torque converter cover, and
the torque converter lock-up clutch is released; the torque converter clutch lock-up is OFF.
＊０２
Power flow
The power flows by way of:
Engine
↓
Drive plate
↓
Torque converter cover
↓
Pump
↓
Turbine
↓
Mainshaft
14-70
ＴＡ０８ＡＥＢＥ１０４７４００００００ＣＡＡＴ０６
TORQUE CONVERTER
CLUTCH PISTON
TORQUE
CONVERTER
COVER
TURBINE
TORQUE
CONVERTER
COVER
MAINSHAFT
DAMPER SPRING
TURBINE
To ATF cooler
INLET OUTLET
MAINSHAFT
PUMP
To ATF cooler
INLET