DTC P0802: Transmission Control System Mil Request Circuit Open: Description
WARNING: This page is about a different car, the 2003 GMC Sierra, 2003 GMC Cab & Chassis Sierra, 2003 Chevrolet Silverado, and 2003 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
The Transmission Control Module (TCM) Malfunction Indicator Lamp (MIL) request circuit signals the Engine Control Module (ECM) that the TCM is requesting MIL illumination.