4L80E Automatic Transmission

OPERATION:

The purpose of the Transmission Converter Clutch (TCC) feature is to eliminate the power loss of the torque converter stage when the vehicle is in a cruise mode. The TCC System uses a solenoid operated valve to couple the engine flywheel to the output shaft of the transmission through the torque converter. This reduces the slippage losses in the converter, which increases fuel economy. For the converter clutch to apply, two conditions must be met.

1. Internal transmission fluid pressure must be correct.
2. The control module completes a ground circuit to energize the TCC solenoid in the transmission, which moves a check ball in the fluid line. This allows the converter clutch to apply, if the hydraulic pressure is correct.