Electronic Control System

WARNING: This page is about a different car, the 2002 Buick Regal, 2002 Buick Century, 2001 Buick Regal, and 2001 Buick Century. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: Faulty engine sensors and actuators may cause transaxle-related DTCs or driveability problems. Engine faults and related DTCs must be diagnosed and repaired before transaxle DTCs are repaired. For additional information on diagnosing and repairing engine-related DTCs, see appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE.

NOTE: Stored DTCs may be retrieved from PCM memory using a factory recommended scan tool. DTCs cannot be retrieved by grounding 16-pin Data Link Connector (DLC). Connecting scan tool into DLC (located under left side of instrument panel) enables user to read DTCs and check system voltages on serial data line.

PCM constantly monitors all electrical circuits. If PCM detects circuit problems or sensors out of range, it will record a DTC. If problem continues for a predetermined time, Malfunction Indicator Light (MIL) will illuminate.

If MIL is illuminated, DTC(s) are currently being detected. If MIL is off, and PCM has detected a circuit or sensor problem, DTC(s) will be stored in computer memory.