DTC U1001 to U1254: Module U1XXX Communication: Notes

WARNING: This page is about a different car, the 2003 Pontiac Aztek and 2003 Buick Rendezvous. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: DTC U1001-U1254 Specifications

Courtesy of GENERAL MOTORS CORP.

When more than one Loss of Communication DTC is set in either one module or in several modules, diagnose the DTCs in the following order:

Current DTCs before history DTCs unless told otherwise in the diagnostic tables.
The DTC which is reported the most times.
From the lowest number DTC to the highest number DTC.