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 Opening and closing the bonnet
Opening the bonnet WARNING: To prevent damage to, or loss of the key, remove the key immediately after opening and swivel the Ford badge back. Note: On vehicles with keyless entry, use the spare key to open the bonnet. See Keyless entry. Closing the bonnet Note: Make sure that the bo ...