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KOEO Self-Test

WARNING: This page does not describe the selected car, but rather 12 other vehicles, including the 1993 Mercury Tracer, 1993 Mercury Topaz, 1993 Mercury Sable, 1993 Mercury Grand Marquis, and 1993 Mercury Cougar. However, it is still accessible from the selected car via links, so may be relevant.

Ensure engine is warmed to normal operating temperature. If engine does not start (or stalls after starting), continue KOEO SELF-TEST. DO NOT depress throttle on gasoline vehicles. Turn ignition off. Wait 10 seconds. Ensure test equipment is properly attached. Turn ignition on (engine off). Record all KOEO and Continuous Memory Codes.

If a Code 11 or 111 (pass code) is not retrieved, service KOEO codes. See SERVICE CODE-TO-TEST MENUS. If PCM will not output codes, go to CIRCUIT TEST QA. If service codes are retrieved: