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Home >> Cadillac >> 2002 >> Escalade EXT >> Repair and Diagnosis >> External Pages >> Different car >> Section 232 (Body Control Modules) >> Diagnostic Tests >> DTC U1500: ONSTAR® (Generation F1) Vehicle Communication Interface Module Internal Malfunction >> Test Procedure
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Test Procedure

WARNING: This page is about a different car, the 2002 Oldsmobile Aurora. However, it is still accessible from the selected car via links, so may be relevant.
  1. If cellular communication diagnostic system check has been performed, go to next step. If cellular communication diagnostic system check has not been performed, perform CELLULAR COMMUNICATION DIAGNOSTIC SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM.
  2. Connect a scan tool to DLC. Retrieve DTCs from VCIM. If DTC U1500 is set as current, go to next step. If DTC U1500 is not current, see DIAGNOSTIC AIDS .
  3. Replace VCIM. See ONSTAR® MODULES  under REMOVAL & INSTALLATION. Perform OnStar® setup procedure. See VEHICLE COMMUNICATION UNIT/VEHICLE INTERFACE UNIT (ONSTAR®) .
  4. Using scan tool, clear DTCs. Operate vehicle within code enable criteria. See CODE ENABLE CRITERIA . If DTC resets, repeat test beginning at step  1.
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