KOEO Self-Test

Ensure engine is at 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 in KOEO portion of test, service KOEO codes at this time. Service any engine codes recorded before servicing transmission codes (codes No. 566 and 629). If PCM will not output codes, see TESTS W/CODES - EEC-IV article in ENGINE PERFORMANCE section. If service codes are retrieved observe the following procedures:

• If CHECK ENGINE or SERVICE ENGINE SOON light is on, service codes in order retrieved.
• On vehicles equipped with DIS and EDIS ignition systems, see SYSTEM/COMPONENT TESTS article in the ENGINE PERFORMANCE section if Continuous Memory Code 211, 212, 215, 216, 217, 232 or 238 is retrieved during KOEO SELF-TEST. Repair ignition system as necessary.
• If vehicle has a no-start condition, go to CIRCUIT TEST AA, AB or AC in appropriate TESTS W/CODES - EEC-IV article in the ENGINE PERFORMANCE section.