DTC P0700: TCM Mil Request: 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 Malfunction Indicator Lamp (MIL) requests circuit signals the Engine Control Module (ECM) that the Transmission Control Module (TCM) is requesting MIL illumination.