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Home >> Cadillac >> 2007 >> Escalade EXT >> Repair and Diagnosis >> External Pages >> Different car >> Section 629 (Data Link Communication System) >> Diagnostic Information and Procedures >> DTC U1001-U1254: Module U1XXX Communication >> Test Description
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Test Description

WARNING: This page is about a different car, the 2003 GMC Sierra, 2003 GMC Cab & Chassis Sierra, 2003 Chevrolet Silverado, and 2003 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.

The number below refers to the step number on the diagnostic table.

  1. 6. The module which was not communicating on the class 2 serial data circuit may have set Loss of Communication DTCs for those modules that it was monitoring.
Fig 1: DTC U1001-U1254 (Steps 1 - 3)
G01576994Courtesy of GENERAL MOTORS CORP.
Fig 2: DTC U1001-U1254 (Steps 4 - 8)
G01576995Courtesy of GENERAL MOTORS CORP.
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