Key On Engine Off (KOEO) Self Test Description

PURPOSE
The Key On Engine Off (KOEO) portion of the self-test looks for normal engine "OFF" sensor and actuator readings and sets a Diagnostic Trouble Codes (DTC) if any out of specification readings are detected.

OPERATION
Any sensor or actuator that is out of limits, open, or shorted will set an ON-DEMAND or HARD fault code. If all sensors are within expected ranges, a code 11 (pass) will be displayed.

After the hard fault codes are displayed a single pulse (displays as a 10) occurs to signal that the next set of continuous memory codes are being displayed.

Continuous memory codes are faults that have occurred during normal vehicle operation and have been stored in the Keep Alive Memory.

INITIATING
KOEO self-test may be initiated manually or with a scan tool. Refer to Key On Engine Off (KOEO) Self Test. Key On Engine Off (KOEO) Self Test


IMPORTANT NOTES
- Vehicle should be at normal operating temperature prior to commencing the test.

- Do not depress the throttle during any KOEO self-test.

- Turn engine "OFF" and wait 10 seconds prior to initiating the test.

- On-Demand (hard) codes are displayed first, followed by a separator pulse, followed by the continuous memory codes.