Engine Controls - Tests W/Codes: Introduction: Notes

NOTE: California and Federal applies to installed emission equipment, which may be verified by underhood emission decal. California emissions may be available in other states. References to California models applies to California emission vehicles.

If no faults were found while performing BASIC DIAGNOSTIC PROCEDURES, proceed with self-diagnostics. If no Diagnostic Trouble Codes (DTC) are present after entering self-diagnostics, proceed to the TESTS W/O CODES article for diagnosis by symptom (i.e., ROUGH IDLE, NO START, etc.).

NOTE: Diagnostic Trouble Codes (DTC's) will be referred to as trouble codes in this article.

NOTE: The Malfunction Indicator Light (MIL) on the instrument panel may also be referred to as CHECK ENGINE light. The MIL may not illuminate when certain failures such as faulty starter signal or A/C switch signal exists, or if certain trouble codes are set.