Key ON, Engine OFF (KOEO) On-Demand Self-Test
WARNING: This page is about a different car, the 2003 Mazda Tribute. However, it is still accessible from the selected car via links, so may be relevant.
Key ON, Engine OFF (KOEO) is a functional test of the PCM performed on demand. A fault must be present at the time of testing for the self-test to detect the fault. This test will perform checks on certain sensor and actuator circuits. A DTC will be output on the data link at the end of the test when requested by the NGS Tester. Only system pass, hard fault code or an incomplete OBD II drive mode will be displayed.