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Key On, Engine Running (KOER) Test: Notes

  1. Start engine and raise speed to 3000 RPM within 20 seconds after start. Hold RPM until initial pulses appear (2-3). Continue holding speed until code pulses begin (10-40 seconds).
  2. Return engine to idle when codes begin. If code 11 is displayed proceed to "Cold Drive Complaint Test". If any code(s) other than code 11 are displayed, perform test for code(s) indicated and repair problem(s) before proceeding to "Cold Drive Complaint Test".
NOTE: If no initial pulses or more than 3 initial pulses occur, perform "Tachometer Lead Test".
NOTE: If voltmeter does not pulse, but shows steady high or low readings, see "Functional Test Not Operating".