Part 3
System Description (Continued)D and D3 Positions: Shifting between 2nd gear and 3rd gear
As the speed of the vehicle reaches the programmed value, the PCM turns shift solenoid valve C ON, and shift solenoid valve C covers the port of the shift solenoid valve C pressure (SC) to shift valve C. Shift solenoid valves A and B remain ON. Shift valve C is moved to the left side to switch the port of line pressure (4) and the CPC A pressure (4A) leading to the 2nd clutch. Shift valve C also uncovers the port of the CPC B pressure (4B) leading to the 3rd clutch. PCM controls A/T clutch pressure control solenoid valves A and B. The A/T clutch pressure control solenoid valve A pressure (56) is applied to CPC valve A, and the A/T clutch pressure control solenoid valve B pressure (57) is applied to CPC valve B. CPC valve B regulates line pressure (4"), and line pressure (4") becomes the CPC B pressure (4B). The CPC B pressure flows to shift valve A via shift valves C and B, and becomes 3rd clutch pressure (30) at shift valve A. The 2nd clutch pressure (20) is changed to CPC pressure mode, and the 3rd clutch is engaged with the CPC pressure mode. The 1st clutch is also engaged, but no power is transmitted because of the one-way clutch.
NOTE: When used, "left" or "right" indicates direction on the hydraulic circuit.
D and D3 Positions: Driving in 3rd gear
PCM turns shift solenoid valve B OFF, and shift solenoid valve B uncovers the port of the shift solenoid valve B pressure (SB) to shift valve B. Shift solenoid valves A and C remain ON. Shift valve B is moved to the right side to switch the port of line pressure (5C), the CPC B pressure (5J) leading to the 3rd clutch, and the 2nd clutch pressure (20) releasing the 2nd clutch pressure. The CPC B pressure (5J) changes to line pressure (5J) and the 3rd clutch pressure (30) is changed to line pressure mode, and the 3rd clutch is engaged with the line pressure mode. The 1st clutch is also engaged, but no power is transmitted because of the one-way clutch.
NOTE: When used, "left" or "right" indicates direction on the hydraulic circuit.
D Position: Shifting between 3rd gear and 4th gear
As the speed of the vehicle reaches the programmed value, the PCM turns shift solenoid valve C OFF, and shift solenoid valve C uncovers the port of the shift solenoid valve C pressure (SC) to shift valve C. Shift solenoid valve A remains ON, and shift solenoid valve B remains OFF. Shift valve C is moved to the right side to switch the port of line pressure (4) and the CPC B pressure (4B) leading to the 3rd clutch. Shift valve C also uncovers the port of the CPC A pressure (4A) leading to the 4th clutch. PCM controls A/T clutch pressure control solenoid valves A and B. The A/T clutch pressure control solenoid valve A pressure (56) is applied to CPC valve A, and the A/T clutch pressure control solenoid valve B pressure (57) is applied to CPC valve B. CPC valve A regulates line pressure (4), and line pressure (4) becomes the CPC A pressure (4A). The CPC A pressure (4A) flows to shift valve B via shift valves C and A, and becomes the 4th clutch pressure (40) at shift valve B. The 3rd clutch pressure (30) is changed to the CPC pressure mode, and the 4th clutch is engaged with the CPC pressure mode. The 1st clutch is also engaged, but no power is transmitted because of the one-way clutch.
NOTE: When used, "left" or "right" indicates direction on the hydraulic circuit.
D Position: Driving in 4th gear
The PCM turns shift solenoid valve A OFF, and shift solenoid valve A covers the port of the shift solenoid valve A pressure (SA) to shift valve A. Shift solenoid valves B and C remain OFF. Shift valve A is moved to the left side to switch the port of line pressure (5B), the CPC A pressure (5A) (5L) leading to the 4th clutch, and the 3rd clutch pressure (30) releasing 3rd clutch pressure. The CPC A pressure (5L) changes to line pressure (5L) and the 4th clutch pressure (40) is changed to line pressure mode, and the 4th clutch is engaged with the line pressure mode. The 1st clutch is also engaged, but no power is transmitted because of the one-way clutch.
NOTE: When used, "left" or "right" indicates direction on the hydraulic circuit.
D Position: Shifting between 4th gear and 5th gear
As the speed of the vehicle reaches the programmed value, the PCM turns shift solenoid valve C ON, and shift solenoid valve C covers the port of shift solenoid valve C pressure (SC) to shift valve C. Shift solenoid valve A remains OFF, and shift solenoid valve C remains ON. Shift valve C is moved to the left side to switch the port of line pressure (4) and the CPC A pressure (4A) leading to the 4th clutch. Shift valve C also uncovers the port of the CPC B pressure (4B) leading to the 5th clutch. PCM controls A/T clutch pressure control solenoid valves A and B. The A/T clutch pressure control solenoid valve A pressure (56) is applied to CPC valve A, and A/T clutch pressure control solenoid valve B pressure (57) is applied to CPC valve B. CPC valve B regulates line pressure (4"), and line pressure (4") becomes CPC B pressure (4B). CPC B pressure (4B) flows to shift valve A via shift valves C and B, and becomes 5th clutch pressure (51) at shift valve A. The 4th clutch pressure (40) is changed to CPC pressure mode, and the 5th clutch is engaged with the CPC pressure mode. The 1st clutch is also engaged, but no power is transmitted because of the one-way clutch.
NOTE: When used, "left" or "right" indicates direction on the hydraulic circuit.
D Position: Driving in 5th gear
The PCM turns shift solenoid valve B ON, and shift solenoid valve B covers the port of the shift solenoid valve B pressure (SB) to shift valve B. Shift solenoid valve A remains OFF, and shift solenoid valve C remains ON. Shift valve B is moved to the left side to switch the port of line pressure (5H), the CPC B pressure (5D)) leading to the 5th clutch, and the 4th clutch pressure (40) releasing 4th clutch pressure. The CPC B pressure (5H) changes to line pressure (5H) and the 5th clutch pressure (51) (50) is changed to line pressure mode, and the 5th clutch is engaged with the line pressure mode. The 1st clutch is also engaged, but no power is transmitted because of the one-way clutch.
NOTE: When used, "left" or "right" indicates direction on the hydraulic circuit.
2 Position
Line pressure (1) regulated by the regulator valve flows to shift solenoid valves. PCM controls the shift solenoid valves ON and OFF. The conditions of the shift solenoid valves and positions of the shift valve are as follows:
^ Shift solenoid valve A is turned ON, and opens the port of the shift solenoid valve A pressure (SA); shift valve A moves to the right side.
^ Shift solenoid valve B is turned ON, and closes the port of the shift solenoid valve B pressure (SB); shift valve B and shift valve E stay on the left side.
^ Shift solenoid valve C is OFF, and opens the port of the shift solenoid valve C pressure (SC); shift valve C moves to the right side and shift valve D stays on the left side.
^ Shift solenoid valve D is OFF or ON, and closes or opens the port of the shift solenoid valve D pressure (SD).
Line pressure (4) becomes the 2nd clutch pressure (20) at the shift valve 9 via the shift valves C and A, and flows to the 2nd clutch. The, 2nd clutch is engaged. The 1st clutch is also engaged, but no power is transmitted because of the one-way clutch.
NOTE: When used, "left" or "right" indicates direction on the hydraulic circuit.
1 Position
Line pressure (1) regulated by the regulator valve flows to shift solenoid valves. The PCM controls the shift solenoid valves ON and OFF. The conditions of the shift solenoid valves and positions of the shift valve are as follows:
^ Shift solenoid valve A is OFF, and closes the port of the shift solenoid valve A pressure (SA); shift valve A stays on the left side.
^ Shift solenoid valve B is turned ON, and closes the port of the shift solenoid valve B pressure (SB); shift valve B and shift valve E stay on the left side.
^ Shift solenoid valve C is turned ON, and closes the port of the shift solenoid valve C pressure (SC); shift valve C and shift valve D stay on the left side.
^ Shift solenoid valve D is OFF, and closes the port of the shift solenoid valve D pressure (SD).
Line pressure (4) becomes the 1st clutch pressure (10) at shift valve D, and flows to the 1st clutch. The 1st clutch is engaged. The PCM controls A/T clutch pressure control solenoid valve C, and the A/T clutch pressure control solenoid valve C pressure (58) is applied to CPC valve C via the lock-up shift valve. CPC valve C regulates line pressure (4), and line pressure (4) becomes the CPC C pressure (4C). The CPC C pressure (4C) flows to shift valve B via shift valves D, E, and C, and becomes the 1st-hold clutch pressure (15) at shift valve B. The 1st-hold clutch pressure (15) is applied to the 1st-hold clutch, and the 1st-hold clutch is engaged.
NOTE: When used, "left" or "right" indicates direction on the hydraulic circuit.
R Position: Shifting to the R position from the P or N position
The PCM controls the shift solenoid valves ON and OFF. The conditions of the shift solenoid valves and positions of the shift valve are as follows:
^ Shift solenoid valve A is OFF, and closes the port of the shift solenoid valve A pressure (SA); shift valve A stays on the left side.
^ Shift solenoid valve B is turned ON, and closes the port of the shift solenoid valve B pressure (SB); shift valve B and shift valve E stay on the left side.
^ Shift solenoid valve C is OFF, and opens the port of the shift solenoid valve C pressure (SC); shift valve C and shift valve D move to the right side.
^ Shift solenoid valve D is turned ON, and opens the port of the shift solenoid valve D pressure (SD); reverse control valve moves to the right side.
The manual valve is moved to the R position, and line pressure (1) becomes line pressure (3) at the manual valve. Line pressure (3) passes through the reverse control valve, and becomes line pressure (3A), then flows to the servo valve. Line pressure (3A) pushes the servo valve to the reverse position. Line pressure (3) also flows to the reverse CPC valve, and becomes reverse CPC pressure (3B) (3"). Reverse CPC pressure (3") becomes the 5th clutch pressure (50) at the manual valve, and the 5th clutch pressure (50) flows to the 5th clutch. The 5th clutch is engaged with reverse CPC pressure mode.
NOTE: When used, "left" or "right" indicates direction on the hydraulic circuit.
R Position: Driving in reverse gear
As the speed of the vehicle reaches the programmed value, the PCM turns shift solenoid valve A ON, and shift solenoid valve A uncovers the port of the shift solenoid valve A pressure (SA) to shift valve A. Shift valve A is moved to the right side to switch the port of line pressure (3') and the reverse CPC pressure (3B) leading to the 5th clutch. Line pressure (3) flows to the manual valve via the servo valve and shift valve A, and becomes the 5th clutch pressure (50) at the manual valve. The 5th clutch pressure (50) flows to the 5th clutch, and the 5th clutch is engaged with the line pressure mode.
Reverse Inhibitor Control
When the R position is selected while the vehicle is moving forward, the PCM outputs to keep shift solenoid valve D OFF so that the shift solenoid valve D pressure (SD) is not applied to the reverse control valve. Line pressure (3) stops at the reverse control valve, and is not applied to the servo valve. No power is transmitted to the reverse direction.
NOTE: When used, "left" or "right" indicates direction on the hydraulic circuit.
P Position
The PCM controls the shift solenoid valves ON and OFF. The conditions of the shift solenoid valves and positions of the shift valve are as follows:
^ Shift solenoid valve A is OFF, and closes the port of the shift solenoid valve A pressure (SA); shift valve A stays on the left side.
^ Shift solenoid valve B is turned ON, and closes the port of the shift solenoid valve B pressure (SB); shift valve B and shift valve E stay on the left side.
^ Shift solenoid valve C is OFF, and opens the port of the shift solenoid valve C pressure (SC); shift valve C and shift valve D move to the right side.
^ Shift solenoid valve D is turned ON, and opens the port of the shift solenoid valve D pressure (SD); reverse control valve moves to the right side.
The manual valve is moved to the P position, and line pressure (1) becomes line pressure (3) at the manual valve. Line pressure (3) passes through the reverse control valve, and becomes line pressure (3A), then flows to the servo valve. Line pressure (3A) pushes the servo valve to the reverse position. Line pressure (3) flows to the manual valve via the reverse CPC valve and shift valve A, and stops at the manual valve. Hydraulic pressure is not applied the clutches.
NOTE: When used, "left" or "right" indicates direction on the hydraulic circuit.
Lock-up System
The lock-up mechanism of the torque converter clutch operates in the D position (2nd, 3rd, 4th, and 5th), and D3 position (2nd and 3rd). 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 crankshaft. Together with the hydraulic control, the PCM optimizes the timing and amount of the lock-up mechanism. When shift solenoid valve D is turned on by the PCM, shift solenoid valve D pressure switches the lock-up shift valve lock-up on and off. A/T clutch pressure control solenoid valve C, the lock-up control valve, and lock-up timing valve control the amount of 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 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 ON, and the mainshaft rotates at the same as the engine.
Torque Converter Clutch Lock-up OFF (Disengaging Torque Converter Clutch)
Fluid entered from the chamber between the torque converter cover and the torque converter clutch piston passes through the torque converter and goes out from 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 clutch lock-up is released; torque converter clutch lock-up OFF.
No Lock-up
The PCM commands shift solenoid valve D to remain OFF, and shift solenoid valve D covers the port of the shift solenoid valve D pressure (SD) to the lock-up shift valve. The lock-up shift valve is in the right side, and uncovers the port leading the torque converter pressure (92) to the left side of the torque converter. The torque converter pressure (92) from regulator valve becomes the torque converter pressure (94) at the lock-up shift valve, and enters into the left side of the torque converter to disengage the torque converter clutch. The torque, converter clutch is OFF.
NOTE: When used, "left" or "right" indicates direction on the hydraulic circuit.
Partial Lock-up
As the speed of the vehicle reaches the programmed value, the PCM turns shift solenoid valve D ON, and shift solenoid valve D uncovers the port of the shift solenoid valve D pressure (SD) to the lock-up shift valve. The lock-up shift valve is moved to the left side to uncover the port of the torque converter pressure (91) leading to the right side of the torque converter to engage the torque converter clutch. The PCM also controls A/T clutch pressure control solenoid valve C, and the A/T clutch pressure control solenoid valve C pressure (58) is applied to the lock-up control valve and lock-up timing valve. When the A/T clutch pressure control solenoid valve C pressure (58) is lower, the torque converter pressure (91) from the lock-up timing valve is lower. The torque converter clutch is engaged partially. The A/T clutch pressure control solenoid valve C pressure (58) increases, and the lock-up timing valve is moved to the left side to uncover the port leading the torque converter pressure to high. Under this condition, the torque converter clutch is engaged by pressure from the right side of the torque converter; this condition is partial lock-up.
NOTE: When used, "left" or "right" indicates direction on the hydraulic circuit.
Full Lock-up
When the vehicle speed further increases, the PCM controls A/T clutch pressure control solenoid valve C to increase the A/T clutch pressure control solenoid valve C pressure (58). The A/T clutch pressure control solenoid valve C pressure (58) is applied to the lock-up control valve and lock-up timing valve, and the lock-up control valve and lock-up timing valve are moved to the left side. The torque converter pressure (94) from the left side of the torque converter releases at the lock-up control valve, and lock-up timing valve uncovers the port of the torque converter pressure (91) leading to the right side of the torque converter. The torque converter back pressure is released fully, and the torque converter clutch is engaged fully.
NOTE: When used, "left" or "right" indicates direction on the hydraulic circuit.
