Control Module: Description and Operation

PURPOSE
The Transmission Control Module (TCM) determines shift and converter lockup timing based on signals from the sensors. The valve body solenoids are activated/deactivated accordingly.

OPERATION
The TCM has a self diagnostic program. Component and circuitry malfunctions can be diagnosed with the DRB III tester. Once a malfunction is noted and stored in TCM memory, it is retained even after the problem has been corrected. To cancel a stored malfunction, simply disconnect and reconnect the "Trans." fuse in the TCM harness.