Lockup Control: Notes

WARNING: This page is about a different car, the 2008 Subaru Tribeca, 2008 Subaru Outback, and 2008 Subaru Legacy. However, it is still accessible from the selected car via links, so may be relevant.

By engaging the lockup clutch in the torque converter, the slip in the torque converter is eliminated and power is transmitted more effectively.
Based on signals from the TCM, the lockup solenoid is controlled in order to let the lockup control valve operate and adjust apply pressure/release pressure, to consequently vary the lockup clutch engagement force.

Lockup operation conditions

Fig 1: Gear Position Chart

Courtesy of SUBARU OF AMERICA, INC.

Fig 2: Flow Chart Of Lockup Control

Courtesy of SUBARU OF AMERICA, INC.