Distribution of Hydraulic Pressure
As the engine turns, the ATF pump starts to operate. Automatic transmission fluid (ATF) is drawn through the ATF strainer (filter) and discharged into the hydraulic circuit. Then, ATF flowing from the ATF pump becomes line pressure that is regulated by the regulator valve. Torque converter pressure from the regulator valve enters the torque converter through the lock-up shift valve and lock-up control valve, and it is discharged from the torque converter. The torque converter check valve prevents torque converter pressure from rising.
The PCM controls shift solenoid valves A, B, C, and D ON and OFF, and the shift solenoid valves control shift solenoid pressure to the shift valves. Applying shift solenoid pressure to the shift valves moves the position of the shift valve, and switches the port of hydraulic pressure. The PCM also controls A/T clutch pressure control solenoid valves A, B, and C. The A/T clutch pressure control solenoid valves regulate hydraulic pressure, and apply the pressure to CPC valves A, B, and C, and the reverse CPC valve.
When shifting between gears, the clutches are engaged by pressure from the CPC pressure mode. The PCM controls one of the shift solenoid valves to move the position of the shift valve. This movement switches the port of CPC pressure and line pressure. Line pressure is then applied to the clutch, and CPC pressure is released. The clutch is engaged with line pressure after shifting is completed.
Hydraulic Pressure at the Port for use in the hydraulic circuit:
| Port | Hydraulic Pressure | Port | Hydraulic Pressure |
|---|---|---|---|
| 1 | Line | SC | Shift solenoid valve C |
| 2 | Line | SC' | Shift solenoid valve C |
| 3 | Line | SD | Shift solenoid valve D |
| 3' | Line | 10 | 1st clutch |
| 3" | Reverse CPC or Line | 15 | 1st-hold clutch |
| 3A | Line | 20 | 2nd clutch |
| 3B | Reverse CPC | 30 | 3rd clutch |
| 4 | Line | 40 | 4th clutch |
| 4' | Line | 50 | 5th clutch |
| 4" | Line | 51 | 5th clutch |
| 4A | CPC A | 56 | A/T clutch pressure control solenoid valve A |
| 4B | CPC B | 57 | A/T clutch pressure control solenoid valve B |
| 4C | CPC C | 5R | A/T clutch pressure control solenoid valve B |
| 5A | CPC A | 58 | A/T clutch pressure control solenoid valve C |
| 5B | CPC A or Line | 90 | Torque converter |
| 5C | CPC B or Line | 90' | Torque converter |
| 5D | CPC B | 91 | Torque converter |
| 5E | CPC C | 91' | Torque converter |
| 5F | CPC C | 92 | Torque converter |
| 5G | CPC C | 93 | ATF cooler |
| 5H | CPC B or Line | 94 | Torque converter |
| 5J | CPC B or Line | 95 | Lubrication |
| 5K | CPC A or Line | 95' | Lubrication |
| 5L | CPC A or Line | 96 | Torque converter |
| 5M | Line | 99 | Suction |
| 5N | CPC C | X | Drain |
| 6 | Modulator | HX | High position drain |
| SA | Shift solenoid valve A | AX | Air drain |
| SB | Shift solenoid valve B | - | - |