Diagnostic Trouble Codes (DTCS)
WARNING: This page is about a different car, the 2000 Buick Park Avenue. However, it is still accessible from the selected car via links, so may be relevant.
Sensing & Diagnostic Module (SDM) provides a record of DTCs, stored according to type. SDM performs diagnostic monitoring of SIR system electrical components and sets a diagnostic trouble code (DTC) when a malfunction is detected. Current DTCs are stored in SDM and are erased when fault is corrected. Current DTCs can be read using a scan tool such as Tech 2.