Electronic Controls
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2003 GMC Sierra, 2003 GMC Cab & Chassis Sierra, 2003 Chevrolet Silverado, 2003 Chevrolet Cab & Chassis Silverado, and 2002 GMC Sierra. However, it is still accessible from the selected car via links, so may be relevant.
A microcomputer provides electronically controlled automatic engagement of the torque converter clutch. The microcomputer is an independent controller and is referred to as a Transmission Control Module (TCM).
The electronic control system uses adaptive logic to provide optimum shift quality. Driving efficiency is improved by shifting at the exact programmed transmission shift point for every engine, transmission, and vehicle combination. The electronic controls can be customized for 4-speed or 5-speed operation to meet vocational requirements.