Torque converter clutch does not disengage
Check for a stored DTC, and check for loose connections.
Test the solenoid valve function with the HDS.
Inspect the A/T clutch pressure control solenoid valve body gasket, ATF feed pipes, and O-rings for wear and damage.
Inspect the O-rings, and check the shift solenoid valve for seizure.
Replace the torque converter assembly.
Check the lock-up shift valve in the regulator valve body for free movement, and check the valve spring for wear and damage.
Check the lock-up control valve in the main valve body for free movement, and check the valve spring for wear and damage.
Shift solenoid valve D defective
A/T clutch pressure control solenoid valve A defective
Torque converter clutch piston defective
Lock-up shift valve defective
Lock-up control valve defective