System Description

WARNING: This page is about a different car, the 2015 Lexus IS 250 and 2014 Lexus IS 250. However, it is still accessible from the selected car via links, so may be relevant.

The ECM uses the signals from the throttle position sensor, air-flow meter, transmission revolution sensor (NT), transmission revolution sensor (SP2) and crankshaft position sensor to monitor the engagement condition of the lock-up clutch.

The ECM compares the engagement condition of the lock-up clutch with the lock-up schedule in the ECM memory to detect mechanical problems of the shift solenoid valve SLU, valve body and torque converter assembly.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	Memory
P2757	Torque Converter Clutch Pressure Control Solenoid Performance (Shift Solenoid Valve SLU)	Lock-up does not occur when driving in the lock-up range (normal driving at 80 km/h [50 mph]), or lock-up remains ON in the lock-up OFF range. (2-trip detection logic)	Shift solenoid valve SLU remains open or closed Valve body is blocked Torque converter assembly Automatic transmission (clutch, brake or gear, etc.) Line pressure is too low	Comes on	DTC stored