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Home >> GMC >> 1999 >> Forward Control 4.3 W, Automatic >> Repair and Diagnosis >> External Pages >> Different car >> Section 170 (Body Control Modules) >> Diagnostic Tests >> DTC U1500: ONSTAR® (Generation F1) Vehicle Communication Interface Module Internal Malfunction >> Code Enable Criteria
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Code Enable Criteria

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.

VCIM microprocessor runs diagnostic program to detect an internal fault during module power up, and every ten seconds, until module re-enters sleep mode.