TCM Inputs: Overview

The TCM uses various inputs to determine when to upshift, or downshift and when to engage or disengage the Torque Converter Clutch (TCC). The TCM also uses these inputs for continuous feedback data for controlling shift quality. Without any input, the TCM has no way to determine the state of the transaxle and cannot control its operation as designed.
Some of the inputs to the TCM are direct, or hardwired inputs, while others are shared with other components through the PCI Bus.