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Home >> Mercury >> 1992 >> Capri Base, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Tests W/Codes >> Quick Tests >> Key On, Engine Running (KOER) Self-Test >> KOER
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Key On, Engine Running (KOER) Self-Test: KOER

  1. Deactivate self-test. Start and run engine at 2000 RPM for 2 minutes to warm up EGO sensor. Turn off engine and wait 10 seconds.
  2. Restart engine, and activate self-test. Record all service codes displayed. See TROUBLE CODE DEFINITION  table. If no codes are present, proceed to SWITCH MONITOR TEST  .