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 Air Distribution and Filtering
Air Distribution and Filtering NOTE: The air distribution system is not designed for use with a cabin air filter. A cabin air filter is not installed from the factory and is not available as a dealer installed accessory. NOTE: The temperature blend door and airflow mode doors are positioned ...