System Description

The clutch pressure control solenoid is controlled by the signals from the switches and sensors. Thus, the clutch pressure is adjusted to be appropriate to the engine load state and vehicle driving state. It becomes possible to finely control the clutch hydraulic pressure with high precision and a smoother shift change characteristic is attained.

Fig 1: Clutch Shift Control Valve Communication Diagram

Courtesy of NISSAN MOTOR CO., U.S.A.

Shift Change

The clutch is controlled with the optimum timing and oil pressure by the engine speed, engine torque information, etc.

Fig 2: Shift Change System Diagram

Courtesy of NISSAN MOTOR CO., U.S.A.

*1: Full phase real-time feedback control monitors movement of gear ratio at gear change, and controls oil pressure in real-time to achieve the best gear ratio.

Blipping Control

This system makes transmission clutch engage readily by controlling (synchronizing) engine revolution according to the (calculation of) engine revolution after shifting down.

• "BLIPPING CONTROL" functions.
  • When downshifting by accelerator pedal depression.
  • When downshifting by the manual mode.
  Fig 3: Accelerator Pedal Operation Chart

  Courtesy of NISSAN MOTOR CO., U.S.A.
• TCM selects "BLIPPING CONTROL" or "NORMAL SHIFT CONTROL" according to the gear position, the selector lever position, the engine torque and the speed when accelerating by pedal depression.
• Engine speed control demand signal is transmitted from TCM to ECM under "BLIPPING CONTROL".
• ECM synchronizes the engine speed according to the engine speed control demand signal.

Fig 4: Blipping Control Graph (Downshifting By Accelerator Pedal Depression)

Courtesy of NISSAN MOTOR CO., U.S.A.

Fig 5: Blipping Control Graph (Downshifting By Manual Mode)

Courtesy of NISSAN MOTOR CO., U.S.A.