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Home >> Mazda >> 2004 >> B2300 Base, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Symptom Troubleshooting [Engine] >> Electronic Engine Control (EEC) System >> Powertrain Control Software >> Failure Mode Effects Management
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Failure Mode Effects Management

Failure Mode Effects Management (FMEM) is an alternate system strategy in the PCM designed to maintain engine operation if one or more sensor inputs fail.

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 operational strategy.

All FMEM sensors display a sequence error message on the WDS or equivalent tester. The message may or may not be followed by KOEO or Continuous Memory DTCs when attempting the KOER Self-Test.