With RPO UM8
WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2005 Isuzu Ascender, 2005 GMC Envoy XUV, 2005 GMC Envoy XL, 2005 GMC Envoy, and 2005 Chevrolet TrailBlazer. However, it is still accessible from the selected car via links, so may be relevant.
If the navigation radio is replaced and a theft locked condition exists, the following procedure must be performed:
Perform the Radio Setup (With RPO UM8) in Entertainment.