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Home >> Chevrolet >> 2001 >> Venture Base, Van Passenger >> Repair and Diagnosis >> External Pages >> Different car >> Section 757 (Data Link Communications System) >> Diagnostic Information and Procedures >> DTC U1001 To U1254: Lost Communication with U1XXX Module >> Test Description

Test Description

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The numbers below refer to the step numbers on the diagnostic table.

1. A module which loses power during an ignition cycle will cause other modules to set Lost Communication DTCs.

2. A module which loses power during an ignition cycle will cause other modules to set Lost Communication DTCs.

3. The malfunction is due to an open in the class 2 serial data circuit or an open in the module.

7. The module which was not communicating may have set Lost Communication DTCs for those modules that it was monitoring.

9. The modules which can communicate indicates the module which cannot communicate. You must clear the DTCs from these modules to avoid future misdiagnosis.

Fig 1: DTC U1001-U1254 Diagnostic Specifications
G01533988Courtesy of GENERAL MOTORS CORP.