ipc gauges not happy after shorted diagnostic connector

[rfelsch10]

My daughters 2005 Bonneville SE has lost accurate gauge function after two of the terminals on the diagnostic connector were shorted together. (Why that happened is a whole other conversation.).
Based on research at Google University (not getting consistant answers), It seems that the ip module was damaged. Is this correct? Is the module part of the instrument cluster, part of the BCM (does it even have a BCM?), or is the IP module a stand alone device? Any help is much appreciated. Thanks.