Circuit Description

WARNING: This page is about a different car, the 2005 Toyota 4Runner. However, it is still accessible from the selected car via links, so may be relevant.

The amount of current flow to the solenoid is controlled by the (*) duty ratio of the ECM output signal. The higher the duty ratio becomes, the higher the lock-up hydraulic pressure becomes during the lock-up operation.

(*) 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: Lock Up-Operation Pressure Vs Current Flow To Solenoid Graph

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Fig 2: Identifying Blinking Pattern (Torque Converter Clutch Pressure Control Solenoid Control)

Fig 3: DTC Trouble Detection Chart