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Key On Engine Off (KOEO) Self Test Description

PURPOSE

The Key On Engine Off (KOEO) Self Test detects faults present at the time of the self test. The test scans for normal engine "OFF" sensor readings. Any sensor that is out of limits, open, or shorted will store On-Demand or Diagnostic Trouble Code(s) (DTC) in a special memory called Keep Alive Memory (KAM) when errors are detected. Codes indicating faults that have not occurred in 40 engine warm-up cycles are automatically erased from KAM.