Self-Diagnostic System: Notes
WARNING: This page is about a different car, the 2002 Pontiac Grand Am and 2002 Oldsmobile Alero. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
Intermittent/history communication and/or IGNITION 1 fault DTCs may be caused by incorrect ignition switch operation. See SERVICE INFORMATION
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NOTE:
DO NOT replace Body Control Module (BCM) unless a DTC remains current after all DTC repair procedures have been performed. DO NOT replace BCM based on history DTCs.
NOTE:
Self-Diagnostic system checks are written specifically for use with Tech 2 scan tool. Other generic scan tools can be used, but may have limited functions.
Body Control Module (BCM) is equipped with a self-diagnostic system, which detects system DTCs or abnormalities. When a malfunction occurs, BCM will store a DTC. Malfunctions are recorded as history/intermittent failures or as current failures. Current DTCs indicate BCM has detected a fault which is currently present. A history DTC indicates that BCM has previously detected a malfunction that is not currently present.
Begin diagnosis of BCM by performing diagnostic system check for system in which customer concern is apparent. Diagnostic system check will direct service technician to correct procedure within BCM section when a malfunction is present. See DIAGNOSTIC SYSTEM CHECK INDEX table.
DIAGNOSTIC SYSTEM CHECK INDEX