Failure Mode Effects Management (FMEM)
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The FMEM system is an alternative strategy in the PCM designed to maintain vehicle operation if there is a concern with one or more critical sensor inputs. When a sensor input is perceived to be out of limits by the PCM, an alternative strategy is initiated. The PCM substitutes a fixed value and continues to monitor the incorrect sensor input. If the suspect sensor operates within limits, the PCM returns to the normal engine running strategy. FMEM operation results in continuous memory DTCs during normal engine operation and when carrying out the key on engine running (KOER) self-test mode.