System Description

WARNING: This page is about a different car, the 2006 Lexus IS 350. However, it is still accessible from the selected car via links, so may be relevant.

The linear solenoid valve (SLT) controls the transmission line pressure for smooth transmission operation based on signals from the throttle position sensor and the vehicle speed sensor. The ECM adjusts the duty ratio (*) of the SLT solenoid valve to control hydraulic line pressure coming from the primary regulator valve. Appropriate line pressure assures smooth shifting with varying engine outputs.

(*): Duty Ratio

The duty ratio is the ratio of the period of continuity in one cycle. For example, if A is the period of continuity in one cycle, and B is the period of non-continuity, then

Duty Ratio=A/(A+B) x 100 (%)

Fig 1: SLT Solenoid Valve Cycle Pattern

DTC TROUBLE DETECTION CONDITION

DTC No.	DTC Detection Condition	Trouble Area
P2714	ECM detects a malfunction on SLT (ON side) according to the revolution difference of the turbine and the output shaft, and also by the oil pressure. (2-trip detection logic)	Shift solenoid valve SLT remains open or closed Shift solenoid valve S1, S2, S3, S4 or SL2 remains open or closed Gear 6 incorrect ratio (reverse sequence valve) or 1-2 shift valve is stuck Valve body is blocked Automatic transmission (clutch, brake or gear, etc.)