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 Principle of operation
Airbags WARNINGS: Do not modify the front of your vehicle in any way. This could adversely affect deployment of the airbags. Original text according to ECE R94.01: Extreme Hazard! Do not use a rearward facing child restraint on a seat protected by an airbag in front of it! Wear a seat ...