Hydraulic Flow (cont'd)
D Position: Driving in 1st gear
The PCM turns shift solenoid valves A ON, and keeps B and C ON, and D and E OFF. Shift solenoid valve A pressure (SA) is applied to right side of shift valve A. Shift valve A is moved to the left side to uncover the line pressure port leading to the 1st clutch, and to cover the A/T clutch pressure control solenoid valve pressure port.
Fluid flows to the 1st clutch by way of:
Line pressure (1) → Shift valve D−Line pressure (1A) → Shift valve A−Line pressure (1B) → Manual valve−Line pressure (5A) → Shift valve C−Line pressure (5B) → Shift valve B−1st clutch pressure (10) → 1st clutch
The 1st clutch pressure (10) is applied to the 1st clutch, and the 1st clutch is engaged securely.
NOTE: When used, ‘‘left'' or ‘‘right'' indicates direction on the hydraulic circuit.
D Position: Shifting between 1st gear and 2nd gear
As the speed of the vehicle reaches the programmed value, the PCM turns shift solenoid valve A OFF, and keeps B and C ON, and D and E OFF. Shift solenoid valve A pressure (SA) in the right side of the shift valve A is released. Shift valve A is moved to the right side to uncover the ports of A/T clutch pressure control solenoid valve pressure leading to the 1st and 2nd clutches. The PCM controls the A/T clutch pressure control solenoid valve to regulate hydraulic pressure. A/T clutch pressure control solenoid valve A pressure (55) changes to 1st clutch pressure (10) at shift valve B, and A/T clutch pressure control solenoid valve B pressure (56) changes to 2nd clutch pressure (20) at shift valve A. The 1st and 2nd clutches are engaged gently.
NOTE: When used, ‘‘left'' or ‘‘right'' indicates direction on the hydraulic circuit.