Low One-way Clutch (Automatic gearbox - JF403E)

Low One-way Clutch

The ’roller type’ low one way clutch locks the anti-clockwise rotation of the front planetary carrier. It operates on drive and in 1st gear. The clutch is free to rotate in a clockwise direction but is prevented from operating in an anti-clockwise direction by the clutch rollers, which lock the inner and outer races.

Forward One-way Clutch

The ’sprag type’ forward one-way clutch operates on drive in 1st, 2nd and 3rd gears.

Brake band

The brake band locks the reverse clutch drum and operates in 2nd and 4th gear.

Electronic Control

Line pressure control

ECU controls line pressure according to throttle opening angle and vehicle driving condition.

Gear shift control

ECU decides correct gear for vehicle driving condition according to vehicle speed, throttle opening angle, shift range and shift pattern. Shift patterns can be changed by pressing ’Sport’ and ’Snow’ mode switches.

Lock-up control

ECU controls lock-up solenoid according to vehicle speed and shift range.

Engine brake control

ECU controls over-run clutch solenoid according to throttle opening angle, vehicle speed, shift range and shift pattern, engaging over-run clutch to provide engine braking.

Torque down control

ECU requires engine ECM to bring down engine torque temporarily during shifting.

’N’ and ’D’ select signal output control

To prevent engine idle speed from dropping below the managed idle speed, the ECU transmits a signal to the engine ECM when the selector is moved from ’N’ to ’D’, ’3’, ’2’ or ’1’ range.

Self diagnosis function

The ECU memories faults, and when self-diagnosis is initiated, the ’Sports’ mode warning light flashes a fault code.

Fail safe function

If a malfunction is detected, the ECU activates a ’back-up’ mode to minimise the effects on vehicle performance.