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DTC U1001 To U1254: Module U1XXX Communication: Notes

WARNING: This page is about a different car, the 2003 Chevrolet Corvette. However, it is still accessible from the selected car via links, so may be relevant.

The module ID Number list provides a method for determining which module is not communicating. A module with an internal class 2 serial data circuit malfunction or which loses power during the current ignition cycle would have a Lost Communication DTC set by other modules. Use the module ID Number list in order to determine which module is not communicating and the DTC U1001-U1254 diagnostic table in order to diagnose the malfunction.

Fig 1: DTC U1001-U1254 System & ID Number Table
G01453105Courtesy of GENERAL MOTORS CORP.