System 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 ECM uses the signals from the throttle position sensor, Airflow meter, turbine (input) speed sensor, output speed sensor and crankshaft position sensor to monitor the engagement condition of the lock-up clutch.

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

Fig 1: Identifying Torque Converter Clutch Pressure Control Solenoid

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Fig 2: Lock Up-Operation Pressure Vs Current Flow To Solenoid Graph

Fig 3: DTC Trouble Detection Chart