Failure Mode Effects Management (FMEM)

Failure Mode Diagnosis. MIL Vehicles Built Before 11-2-87:

MIL Vehicles Built Before 11-2-87

Failure Mode Diagnosis. Non MIL Vehicles:

Non MIL Vehicles

Failure Mode Diagnosis. Vehicles Built After 11-2-87 (Part 1 of 2):

Vehicles Built After 11-2-87 (Part 1 of 2)

Failure Mode Diagnosis. Vehicles Built After 11-2-87 (Part 2 of 2):

Vehicles Built After 11-2-87 (Part 2 of 2)


Failure mode effects management is an alternate strategy in the electronic control assembly (ECA), designed to allow improved vehicle operation should one or more sensor inputs fail.
When a sensor input is perceived to be out of limits by the ECA, an alternative strategy will be initiated. The ECA will substitute a fixed in limit sensor value and will continue to monitor the faulty sensor input. If the faulty sensor operates within limits, the ECA will return to the normal engine running strategy. The malfunction indicator light (check engine light) will remain ON when failure mode effects management is in effect.