Circuit/System Description

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The torque converter clutch (TCC) pressure control (PC) solenoid is part of the control solenoid (w/body and TCM) valve assembly and is not serviced separately. The TCC PC solenoid is a normally low pressure control solenoid. The actuator feed limit (AFL) valve supplies transmission fluid to the TCC PC solenoid. The TCC PC solenoid supplies transmission fluid to the TCC regulator valve in the lower valve body and the TCC control valve in the pump. When conditions are correct to apply the converter clutch, the TCM will increase TCC PC current flow (duty cycle) thereby increasing pressure to move the TCC control valve into the apply position. When the TCC is fully applied, the engine is coupled directly to the transmission. TCC release is accomplished by the TCM decreasing current flow, dropping the apply pressure allowing the TCC control valve to move to the release position.