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Home >> Mazda >> 2004 >> Tribute ES, FWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 483 (Symptom Troubleshooting [Engine Control System]) >> Electronic Engine Control (EEC) System >> Powertrain Control Hardware >> Hardware Limited Operation Strategy (HLOS)
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Hardware Limited Operation Strategy (HLOS)

WARNING: This page is about a different car, the 2005 Mazda Tribute. However, it is still accessible from the selected car via links, so may be relevant.

This system of special circuitry provides minimal engine operation should the PCM [mainly the central processing unit (CPU) or FEEPROM] stop functioning correctly. All modes of Self-Test are not functional at this time. Electronic hardware is in control of the system while in HLOS.

HLOS Allowable Output Functions:

HLOS Disabled Outputs To Default State:

PCM Location