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Home >> Lincoln >> 1989 >> Mark VII LSC >> Repair and Diagnosis >> Engine Performance >> System >> 5.0L CEC Tests W/Codes >> Quick Test >> Key On Engine Off (KOEO) Self-Test >> Test Procedure
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Test Procedure

NOTE: This test procedures has been revised based on updated procedures in Ford Technical Service Bulletin, 89-18A-10.
  1. Turn ignition switch to "OFF" position. Ensure all procedures of VISUAL CHECK & VEHICLE PREPARATION  and EQUIPMENT HOOK-UP  have been followed. Engine should be at normal operating temperature.
  2. Activate the KOEO Self-Test.
  3. Turn ignition switch to the "ON" position.
    • If Star Tester is being used latch center button in down position at this time.
    • If using an analog VOM, connect a jumper wire from Self-Test Input (STI) pigtail to pin No. 2 (Signal Return) on Self-Test connector. See Figure and Figure .
    • If using "Check Engine" (MIL) light, connect a jumper wire from Self-Test Input (STI) pigtail to pin No. 2 (Signal Return) on Self-Test connector. This will activate the KOEO Self-Test, "Check Engine" (MIL) light will start to flash. See Figure and Figure .
    4. NOTE: DO NOT depress the throttle during the KOEO SELF-TEST.
  4. The ECA will run through a test cycle, opening and closing various solenoids and switches. After the completion of the test cycle the codes will appear. Record all codes.
  5. A KOEO Code 11 indicates the system has passed the self-test. A Code 11 must be present before continuing. Disregard any Continuous Memory Codes at this time. Service KOEO codes in the order they appear. Refer to the KOEO SELF-TEST CODES table to find the appropriate CIRCUIT TEST. After each repair, repeat KOEO SELF-TEST until a Code 11 is displayed.
  6. If no KOEO codes are displayed, a Code 11 (pass code) and a Code 10 (separator pulse) are present, record the Continuous Memory Codes. Service only the KOEO CONTINUOUS MEMORY CODE EXCEPTIONS at this time. All other Continuous Memory Codes will be serviced after a Code 11 is displayed during the KOER SELF-TEST.
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