Hard Failures

Hard failures cause Malfunction Indicator Light (MIL) to glow and remain on until malfunction is repaired. If MIL comes on and remains on (MIL may flash) during vehicle operation, cause of malfunction may be determined by using fault codes. See FAULT CODES  . If a sensor fails, ECM will use a substitute value in its calculations to continue engine operation. In this condition, vehicle is functional, but loss of good driveability may result.