Ford Focus Owners Manual: Principle of operation

Engine immobiliser

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Coded keys

Note: Do not shield your keys with metal objects. This may prevent the receiver from recognising your key as a valid one. Note: Have all of your remaining keys erased and recoded if you lose a key ...

More about Ford Focus:

Ford Focus Resetting The Keep Alive Memory (KAM)
Description Resetting the KAM returns the powertrain control module (PCM) memory to its default setting. Adaptive learning contents such as adaptive airflow, idle speed, refueling event, and fuel trim are included. Clearing the continuous diagnostic trouble codes (DTCs) and resetting the emis ...