Diagnostic Aids
WARNING: This page is about a different car, the 1999 Buick Regal and 1999 Buick Century. However, it is still accessible from the selected car via links, so may be relevant.
The following conditions may cause an intermittent: Intermittent short to ground in class 2 serial data link or internal short to ground in BCM. Since BCM sends DTC information to scan tool using class 2 data line, scan tool will be unable to communicate with BCM if DTC is current. If scan tool records a DTC U1301, it is a history code.