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Home >> Lincoln >> 1987 >> Mark VII Base >> Repair and Diagnosis >> External Pages >> Different car >> Section 1 (2.5L HSC/CFI Testing) >> Quick Test >> Key On/Engine Off (KOEO) Self-Test >> Code Output
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Code Output

WARNING: This page is about a different car, the 1987 Ford Taurus. However, it is still accessible from the selected car via links, so may be relevant.

Correct test results for system are dependent on the correct operation of several related non-EEC components and systems. It may be necessary to correct faults in these areas before EEC-IV will pass QUICK TEST  .

Verify that vehicle has been properly prepared. See PREPARATION  and EQUIPMENT HOOK-UP  . Turn ignition on to start SELF-TEST. DO NOT  depress throttle during test. Observe and record all service codes.

  1. If engine does not start, go to TEST A - NO START  , step 1). If KEY ON/ENGINE OFF (KOEO) code and continuous memory indicate a pass (code 11), go to TIMING CHECK  .
  2. If any KOEO code is displayed with continuous memory code 11, KOEO SELF-TEST indicates a fault. Record codes and go to TEST RESULTS & ACTION TO TAKE in this test.
  3. If any (KOEO) or any continuous memory code is displayed, (KOEO) SELF-TEST and continuous memory indicate a fault. Record codes, but DO NOT  repair continuous memory codes at this time. All (KOEO) and KEY ON/ENGINE RUNNING (KOER) SELF-TEST  codes MUST be repaired first. Go to TEST RESULTS & ACTION TO TAKE in this test.
  4. If (KOEO) code 11 displayed with ANY continuous memory code (except 15), continuous memory indicates a fault. Record codes, but DO NOT  repair continuous memory codes at this time. (KOEO) and (KOER) SELF-TEST codes MUST be repaired first. Go to TIMING CHECK  . If engine idles rough, go to DIAGNOSIS BY SYMPTOM TEST  .
  5. If (KOEO) code 11 is displayed and continuous memory code is 15, go to TEST PP - NO CODES/CODES NOT LISTED  , step 9). If no codes are displayed, repeat SELF-TEST to verify that no service codes are present. If codes are not displayed, go to TEST PP - NO CODES/CODES NOT LISTED  , step 1).
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