WARNING: This page is about a different car, the 2004 Dodge Dakota. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: U0101-No Bus Message From Trans Control Module - Diagnostic Procedure (Test Steps 1 - 2)
Courtesy of DAIMLERCHRYSLER CORP.
Fig 2: U0101-No Bus Message From Trans Control Module - Diagnostic Procedure (Test Step 3)