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Home >> Chevrolet >> 2002 >> Impala LS >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 1 (Engine Control System Self-Diagnostics - 3.4L) >> Self-Diagnostic System >> On-Board Diagnostics >> Notes
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On-Board Diagnostics: Notes

WARNING: This page is about a different variant/trim than selected.

PCM is equipped with a self-diagnostic system which detects system failures or abnormalities. When a malfunction occurs, PCM will store a Diagnostic Trouble Code (DTC) and, if code is emissions related, the Malfunction Indicator Light (MIL) located on instrument cluster will illuminate.

There are 2 paths for accessing on-board diagnostics. It is necessary to access information through both paths, as each path presents some different information.