Key On Engine Off (KOEO) Self-Test

WARNING: This page is about a different car, the 2001 Mercury Villager. However, it is still accessible from the selected car via links, so may be relevant.

These DTCs indicate faults are present at time of testing. A hard fault may cause CHECK ENGINE or MIL to illuminate and remain illuminated until fault is repaired. If KOEO DTCs are retrieved during a KOEO SELF-TEST, identify DTCs and perform appropriate diagnostic test. See DIAGNOSTIC TROUBLE CODE DEFINITIONS .

SYSTEM PASS indicates no DTCs were recorded in that portion of test. If SYSTEM PASS is not retrieved in KOEO SELF-TEST, DTCs retrieved during KOER SELF-TEST may not be valid.

Ensure engine is at normal operating temperature. If engine does not start (or stalls after starting), continue KOEO SELF-TEST. Turn ignition switch to OFF position. Ensure test equipment is properly attached. Program NGS tester following manufacturers instructions. Follow operating instructions from NGS tester menu.