KOEO & KOER Codes (Hard Faults)

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