Hydraulic Flow (cont'd)
Shifting between 1st gear and 2nd gear in D and S with automatic shift mode
As the speed of the vehicle reaches the programmed value, the PCM turns shift solenoid valve A OFF, and B and C remain ON, and D and E remain OFF. Shift solenoid valve A pressure (SA) in the right side of shift valve A is released. Shift valve A moves to the right side uncovering the A/T clutch pressure control solenoid valve pressure port leading to the 1st and 2nd clutches. The PCM controls the A/T clutch pressure control solenoid valves 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.
Driving in 2nd gear in D and S with automatic shift mode
The PCM turns shift solenoid valves C OFF, D ON, and A and E remain OFF, and B remains ON. Shift solenoid valve C pressure (SC) in the right side of shift valve C is released. Shift valve C moves to the right side to switch the ports. This movement covers the A/T clutch pressure control solenoid valve pressure ports to stop at shift valves C and A, and uncover the line pressure port leading to the 2nd clutch.
Fluid flows to 2nd clutch by way of:
Line pressure (1) → Manual valve−Line pressure (4) → Shift valve C−Line pressure (5E) → Shift valve B−Line pressure (5F) → Shift valve A−2nd clutch pressure (20) → 2nd clutch
2nd clutch pressure (20) is applied to the 2nd clutch, and the 2nd clutch is engaged securely.
NOTE: When used, ‘‘left'' or ‘‘right'' indicates direction on the hydraulic circuit.