Mobile Identification Number and Mobile Directory Number
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2003 GMC Yukon XL, 2003 GMC Yukon, 2003 Chevrolet Tahoe, 2003 Chevrolet Suburban, and 2003 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.
The Generation 5 VCIM utilizes two numbers for cellular device identification, call routing and connection, a MIN (Mobile Identification Number) and a MDN (Mobile Directory Number). The MIN represents the number used by the cellular carrier for call routing purposes while the MDN represents the number dialed to reach the cellular devise. Although technicians have the capability to change these numbers by means of the scan tool, this should ONLY be done at the direction of and with explicit instruction from the General Motors Technical Assistance Center (GM TAC).